diff --git a/extern/storage-sealing/fsm.go b/extern/storage-sealing/fsm.go
index 0e3f6ba2b..a1739a1cc 100644
--- a/extern/storage-sealing/fsm.go
+++ b/extern/storage-sealing/fsm.go
@@ -50,6 +50,7 @@ var fsmPlanners = map[SectorState]func(events []statemachine.Event, state *Secto
 	),
 	AddPiece: planOne(
 		on(SectorPieceAdded{}, WaitDeals),
+		apply(SectorStartPacking{}),
 	),
 	Packing: planOne(on(SectorPacked{}, GetTicket)),
 	GetTicket: planOne(
@@ -447,56 +448,72 @@ func final(events []statemachine.Event, state *SectorInfo) (uint64, error) {
 	return 0, xerrors.Errorf("didn't expect any events in state %s, got %+v", state.State, events)
 }
 
-func on(mut mutator, next SectorState) func() (mutator, func(*SectorInfo) error) {
-	return func() (mutator, func(*SectorInfo) error) {
-		return mut, func(state *SectorInfo) error {
+func on(mut mutator, next SectorState) func() (mutator, func(*SectorInfo) (bool, error)) {
+	return func() (mutator, func(*SectorInfo) (bool, error)) {
+		return mut, func(state *SectorInfo) (bool, error) {
 			state.State = next
-			return nil
+			return false, nil
 		}
 	}
 }
 
-func onReturning(mut mutator) func() (mutator, func(*SectorInfo) error) {
-	return func() (mutator, func(*SectorInfo) error) {
-		return mut, func(state *SectorInfo) error {
+// like `on`, but doesn't change state
+func apply(mut mutator) func() (mutator, func(*SectorInfo) (bool, error)) {
+	return func() (mutator, func(*SectorInfo) (bool, error)) {
+		return mut, func(state *SectorInfo) (bool, error) {
+			return true, nil
+		}
+	}
+}
+
+func onReturning(mut mutator) func() (mutator, func(*SectorInfo) (bool, error)) {
+	return func() (mutator, func(*SectorInfo) (bool, error)) {
+		return mut, func(state *SectorInfo) (bool, error) {
 			if state.Return == "" {
-				return xerrors.Errorf("return state not set")
+				return false, xerrors.Errorf("return state not set")
 			}
 
 			state.State = SectorState(state.Return)
 			state.Return = ""
-			return nil
+			return false, nil
 		}
 	}
 }
 
-func planOne(ts ...func() (mut mutator, next func(*SectorInfo) error)) func(events []statemachine.Event, state *SectorInfo) (uint64, error) {
+func planOne(ts ...func() (mut mutator, next func(*SectorInfo) (more bool, err error))) func(events []statemachine.Event, state *SectorInfo) (uint64, error) {
 	return func(events []statemachine.Event, state *SectorInfo) (uint64, error) {
-		if gm, ok := events[0].User.(globalMutator); ok {
-			gm.applyGlobal(state)
-			return 1, nil
-		}
+		for i, event := range events {
+			if gm, ok := event.User.(globalMutator); ok {
+				gm.applyGlobal(state)
+				return uint64(i + 1), nil
+			}
 
-		for _, t := range ts {
-			mut, next := t()
+			for _, t := range ts {
+				mut, next := t()
 
-			if reflect.TypeOf(events[0].User) != reflect.TypeOf(mut) {
+				if reflect.TypeOf(event.User) != reflect.TypeOf(mut) {
+					continue
+				}
+
+				if err, iserr := event.User.(error); iserr {
+					log.Warnf("sector %d got error event %T: %+v", state.SectorNumber, event.User, err)
+				}
+
+				event.User.(mutator).apply(state)
+				more, err := next(state)
+				if err != nil || !more {
+					return uint64(i + 1), err
+				}
+			}
+
+			_, ok := event.User.(Ignorable)
+			if ok {
 				continue
 			}
 
-			if err, iserr := events[0].User.(error); iserr {
-				log.Warnf("sector %d got error event %T: %+v", state.SectorNumber, events[0].User, err)
-			}
-
-			events[0].User.(mutator).apply(state)
-			return 1, next(state)
+			return uint64(i + 1), xerrors.Errorf("planner for state %s received unexpected event %T (%+v)", state.State, event.User, event)
 		}
 
-		_, ok := events[0].User.(Ignorable)
-		if ok {
-			return 1, nil
-		}
-
-		return 0, xerrors.Errorf("planner for state %s received unexpected event %T (%+v)", state.State, events[0].User, events[0])
+		return uint64(len(events)), nil
 	}
 }
diff --git a/extern/storage-sealing/fsm_events.go b/extern/storage-sealing/fsm_events.go
index 969ccf1e2..f9c1553e3 100644
--- a/extern/storage-sealing/fsm_events.go
+++ b/extern/storage-sealing/fsm_events.go
@@ -1,13 +1,16 @@
 package sealing
 
 import (
-	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
+	"time"
+
 	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/specs-storage/storage"
+
+	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
 )
 
 type mutator interface {
@@ -81,6 +84,9 @@ type SectorAddPiece struct {
 }
 
 func (evt SectorAddPiece) apply(state *SectorInfo) {
+	if state.CreationTime.IsZero() {
+		state.CreationTime = time.Now()
+	}
 	state.PendingPieces = append(state.PendingPieces, evt.NewPiece)
 }
 
diff --git a/extern/storage-sealing/input.go b/extern/storage-sealing/input.go
index b0d06b326..0361f5c08 100644
--- a/extern/storage-sealing/input.go
+++ b/extern/storage-sealing/input.go
@@ -3,6 +3,7 @@ package sealing
 import (
 	"context"
 	"sort"
+	"time"
 
 	"golang.org/x/xerrors"
 
@@ -21,9 +22,35 @@ func (m *Sealing) handleWaitDeals(ctx statemachine.Context, sector SectorInfo) e
 	// if full / oldish / has oldish deals goto seal
 	// ^ also per sector deal limit
 
-	// send SectorStartPacking
-
 	m.inputLk.Lock()
+
+	now := time.Now()
+	st := m.sectorTimers[m.minerSectorID(sector.SectorNumber)]
+	if st != nil {
+		if !st.Stop() { // timer expired, SectorStartPacking was/is being sent
+			// we send another SectorStartPacking in case one was sent in the handleAddPiece state
+			return ctx.Send(SectorStartPacking{})
+		}
+	}
+
+	if !sector.CreationTime.IsZero() {
+		cfg, err := m.getConfig()
+		if err != nil {
+			return xerrors.Errorf("getting storage config: %w", err)
+		}
+
+		sealTime := sector.CreationTime.Add(cfg.WaitDealsDelay)
+		if now.After(sealTime) {
+			return ctx.Send(SectorStartPacking{})
+		} else {
+			m.sectorTimers[m.minerSectorID(sector.SectorNumber)] = time.AfterFunc(sealTime.Sub(now), func() {
+				if err := ctx.Send(SectorStartPacking{}); err != nil {
+					log.Errorw("sending SectorStartPacking event failed", "sector", sector.SectorNumber, "error", err)
+				}
+			})
+		}
+	}
+
 	var used abi.UnpaddedPieceSize
 	for _, piece := range sector.Pieces {
 		used += piece.Piece.Size.Unpadded()
@@ -32,7 +59,7 @@ func (m *Sealing) handleWaitDeals(ctx statemachine.Context, sector SectorInfo) e
 	m.openSectors[m.minerSectorID(sector.SectorNumber)] = &openSector{
 		used: used,
 		maybeAccept: func(cid cid.Cid) error {
-			// todo check space
+			// todo double check space
 
 			// todo check deal expiration
 
@@ -62,6 +89,13 @@ func (m *Sealing) handleAddPiece(ctx statemachine.Context, sector SectorInfo) er
 
 	res := SectorPieceAdded{}
 
+	var offset abi.UnpaddedPieceSize
+	pieceSizes := make([]abi.UnpaddedPieceSize, len(sector.Pieces))
+	for i, p := range sector.Pieces {
+		pieceSizes[i] = p.Piece.Size.Unpadded()
+		offset += p.Piece.Size.Unpadded()
+	}
+
 	for _, piece := range sector.PendingPieces {
 		m.inputLk.Lock()
 		deal, ok := m.pendingPieces[piece]
@@ -72,23 +106,13 @@ func (m *Sealing) handleAddPiece(ctx statemachine.Context, sector SectorInfo) er
 			return xerrors.Errorf("piece %s assigned to sector %d not found", piece, sector.SectorNumber)
 		}
 
-		var stored abi.PaddedPieceSize
-		for _, piece := range sector.Pieces {
-			stored += piece.Piece.Size
-		}
+		pads, padLength := ffiwrapper.GetRequiredPadding(offset.Padded(), deal.size.Padded())
 
-		pads, padLength := ffiwrapper.GetRequiredPadding(stored, deal.size.Padded())
-
-		if stored+padLength+deal.size.Padded() > abi.PaddedPieceSize(ssize) {
+		if offset.Padded()+padLength+deal.size.Padded() > abi.PaddedPieceSize(ssize) {
 			return xerrors.Errorf("piece assigned to a sector with not enough space")
 		}
 
-		offset := padLength
-		pieceSizes := make([]abi.UnpaddedPieceSize, len(sector.Pieces))
-		for i, p := range sector.Pieces {
-			pieceSizes[i] = p.Piece.Size.Unpadded()
-			offset += p.Piece.Size
-		}
+		offset += padLength.Unpadded()
 
 		for _, p := range pads {
 			ppi, err := m.sealer.AddPiece(sectorstorage.WithPriority(ctx.Context(), DealSectorPriority),
@@ -115,9 +139,13 @@ func (m *Sealing) handleAddPiece(ctx statemachine.Context, sector SectorInfo) er
 			return xerrors.Errorf("writing padding piece: %w", err) // todo failed state
 		}
 
+		deal.accepted(sector.SectorNumber, offset, nil)
+
+		offset += deal.size
 		pieceSizes = append(pieceSizes, deal.size)
+
 		res.NewPieces = append(res.NewPieces, Piece{
-			Piece: ppi,
+			Piece:    ppi,
 			DealInfo: &deal.deal,
 		})
 	}
@@ -155,7 +183,11 @@ func (m *Sealing) AddPieceToAnySector(ctx context.Context, size abi.UnpaddedPiec
 		return 0, 0, xerrors.Errorf("piece for deal %s already pending", *deal.PublishCid)
 	}
 
-	resCh := make(chan struct{sn abi.SectorNumber; offset abi.UnpaddedPieceSize; err error}, 1)
+	resCh := make(chan struct {
+		sn     abi.SectorNumber
+		offset abi.UnpaddedPieceSize
+		err    error
+	}, 1)
 
 	m.pendingPieces[*deal.PublishCid] = &pendingPiece{
 		size:     size,
@@ -164,9 +196,9 @@ func (m *Sealing) AddPieceToAnySector(ctx context.Context, size abi.UnpaddedPiec
 		assigned: false,
 		accepted: func(sn abi.SectorNumber, offset abi.UnpaddedPieceSize, err error) {
 			resCh <- struct {
-				sn   abi.SectorNumber
+				sn     abi.SectorNumber
 				offset abi.UnpaddedPieceSize
-				err  error
+				err    error
 			}{sn: sn, offset: offset, err: err}
 		},
 	}
@@ -203,15 +235,15 @@ func (m *Sealing) updateInput(ctx context.Context, sp abi.RegisteredSealProof) e
 
 	// todo: this is distinctly O(n^2), may need to be optimized for tiny deals and large scale miners
 	//  (unlikely to be a problem now)
-	for id, sector := range m.openSectors {
-		avail := abi.PaddedPieceSize(ssize).Unpadded() - sector.used
+	for pieceCid, piece := range m.pendingPieces {
+		if piece.assigned {
+			continue // already assigned to a sector, skip
+		}
 
-		for pieceCid, piece := range m.pendingPieces {
-			if piece.assigned {
-				continue // already assigned to a sector, skip
-			}
+		toAssign[pieceCid] = struct{}{}
 
-			toAssign[pieceCid] = struct{}{}
+		for id, sector := range m.openSectors {
+			avail := abi.PaddedPieceSize(ssize).Unpadded() - sector.used
 
 			if piece.size <= avail { // (note: if we have enough space for the piece, we also have enough space for inter-piece padding)
 				matches = append(matches, match{
@@ -222,10 +254,8 @@ func (m *Sealing) updateInput(ctx context.Context, sp abi.RegisteredSealProof) e
 					padding: avail % piece.size,
 				})
 			}
-
 		}
 	}
-
 	sort.Slice(matches, func(i, j int) bool {
 		if matches[i].padding != matches[j].padding { // less padding is better
 			return matches[i].padding < matches[j].padding
@@ -266,8 +296,9 @@ func (m *Sealing) updateInput(ctx context.Context, sp abi.RegisteredSealProof) e
 	}
 
 	if len(toAssign) > 0 {
-		m.tryCreateDealSector(ctx, sp)
-
+		if err := m.tryCreateDealSector(ctx, sp); err != nil {
+			log.Errorw("Failed to create a new sector for deals", "error", err)
+		}
 	}
 
 	return nil
@@ -279,13 +310,12 @@ func (m *Sealing) tryCreateDealSector(ctx context.Context, sp abi.RegisteredSeal
 		return xerrors.Errorf("getting storage config: %w", err)
 	}
 
-	if cfg.MaxSealingSectorsForDeals > 0 {
-		if m.stats.curSealing() > cfg.MaxSealingSectorsForDeals {
-			return nil
-		}
-		if m.stats.curStaging() > cfg.MaxWaitDealsSectors {
-			return nil
-		}
+	if cfg.MaxSealingSectorsForDeals > 0 && m.stats.curSealing() > cfg.MaxSealingSectorsForDeals {
+		return nil
+	}
+
+	if cfg.MaxWaitDealsSectors > 0 && m.stats.curStaging() > cfg.MaxWaitDealsSectors {
+		return nil
 	}
 
 	// Now actually create a new sector
@@ -306,3 +336,7 @@ func (m *Sealing) tryCreateDealSector(ctx context.Context, sp abi.RegisteredSeal
 		SectorType: sp,
 	})
 }
+
+func (m *Sealing) StartPacking(sid abi.SectorNumber) error {
+	return m.sectors.Send(uint64(sid), SectorStartPacking{})
+}
diff --git a/extern/storage-sealing/sealing.go b/extern/storage-sealing/sealing.go
index ce54b8a9e..6f4ed0976 100644
--- a/extern/storage-sealing/sealing.go
+++ b/extern/storage-sealing/sealing.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"sync"
+	"time"
 
 	"github.com/ipfs/go-cid"
 	"github.com/ipfs/go-datastore"
@@ -85,6 +86,7 @@ type Sealing struct {
 
 	inputLk       sync.Mutex
 	openSectors   map[abi.SectorID]*openSector
+	sectorTimers  map[abi.SectorID]*time.Timer
 	pendingPieces map[cid.Cid]*pendingPiece
 
 	upgradeLk sync.Mutex
diff --git a/extern/storage-sealing/types.go b/extern/storage-sealing/types.go
index 762fe227a..3f9f55b74 100644
--- a/extern/storage-sealing/types.go
+++ b/extern/storage-sealing/types.go
@@ -3,8 +3,8 @@ package sealing
 import (
 	"bytes"
 	"context"
-
 	"github.com/ipfs/go-cid"
+	"time"
 
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
@@ -70,6 +70,7 @@ type SectorInfo struct {
 	SectorType abi.RegisteredSealProof
 
 	// Packing
+	CreationTime  time.Time
 	Pieces        []Piece
 	PendingPieces []cid.Cid
 
diff --git a/node/modules/storageminer.go b/node/modules/storageminer.go
index f459cf2c4..64f62d6ae 100644
--- a/node/modules/storageminer.go
+++ b/node/modules/storageminer.go
@@ -805,7 +805,7 @@ func NewSetSealConfigFunc(r repo.LockedRepo) (dtypes.SetSealingConfigFunc, error
 				MaxSealingSectors:         cfg.MaxSealingSectors,
 				MaxSealingSectorsForDeals: cfg.MaxSealingSectorsForDeals,
 				WaitDealsDelay:            config.Duration(cfg.WaitDealsDelay),
-				TargetWaitDealsSectors: cfg.TargetWaitDealsSectors,
+				TargetWaitDealsSectors:    cfg.TargetWaitDealsSectors,
 			}
 		})
 		return
@@ -820,7 +820,7 @@ func NewGetSealConfigFunc(r repo.LockedRepo) (dtypes.GetSealingConfigFunc, error
 				MaxSealingSectors:         cfg.Sealing.MaxSealingSectors,
 				MaxSealingSectorsForDeals: cfg.Sealing.MaxSealingSectorsForDeals,
 				WaitDealsDelay:            time.Duration(cfg.Sealing.WaitDealsDelay),
-				TargetWaitDealsSectors: cfg.Sealing.TargetWaitDealsSectors,
+				TargetWaitDealsSectors:    cfg.Sealing.TargetWaitDealsSectors,
 			}
 		})
 		return