Try #4893:

activation/activation.go

@@ -622,12 +622,8 @@ func (b *Builder) poetRoundStart(epoch types.EpochID) time.Time {
 
 func (b *Builder) createAtx(ctx context.Context, challenge *types.NIPostChallenge) (*types.ActivationTx, error) {
 	pubEpoch := challenge.PublishEpoch
-	nextPoetRoundStart := b.poetRoundStart(pubEpoch)
 
-	// NiPoST must be ready before start of the next poet round.
-	buildingNipostCtx, cancel := context.WithDeadline(ctx, nextPoetRoundStart)
-	defer cancel()
-	nipost, postDuration, err := b.nipostBuilder.BuildNIPost(buildingNipostCtx, challenge)
+	nipost, postDuration, err := b.nipostBuilder.BuildNIPost(ctx, challenge)
 	if err != nil {
 		return nil, fmt.Errorf("build NIPost: %w", err)
 	}

activation/nipost.go

@@ -229,15 +229,12 @@ func (nb *NIPostBuilder) BuildNIPost(ctx context.Context, challenge *types.NIPos
 		defer cancel()
 		poetRequests := nb.submitPoetChallenges(submitCtx, prefix, challengeHash.Bytes(), signature, nb.signer.NodeID())
 		if len(poetRequests) == 0 {
-			return nil, 0, &PoetSvcUnstableError{msg: "failed to submit challenge to any PoET", source: ctx.Err()}
+			return nil, 0, &PoetSvcUnstableError{msg: "failed to submit challenge to any PoET", source: submitCtx.Err()}
 		}
 
 		nb.state.Challenge = challengeHash
 		nb.state.PoetRequests = poetRequests
 		nb.persistState()
-		if err := ctx.Err(); err != nil {
-			return nil, 0, fmt.Errorf("submitting challenges: %w", err)
-		}
 	}
 
 	// Phase 1: query PoET services for proofs
@@ -264,11 +261,18 @@ func (nb *NIPostBuilder) BuildNIPost(ctx context.Context, challenge *types.NIPos
 	// Phase 2: Post execution.
 	var postGenDuration time.Duration = 0
 	if nb.state.NIPost.Post == nil {
+		publishDeadline := nb.layerClock.LayerToTime(challenge.TargetEpoch().FirstLayer())
+		if poetProofDeadline.Before(now) {
+			return nil, 0, fmt.Errorf("%w: deadline to publish ATX for pub epoch %d exceeded (deadline: %s, now: %s)", ErrATXChallengeExpired, challenge.PublishEpoch, publishDeadline, now)
+		}
+		publishCtx, cancel := context.WithDeadline(ctx, publishDeadline)
+		defer cancel()
+
 		nb.log.With().Info("starting post execution", log.Binary("challenge", nb.state.PoetProofRef[:]))
 		startTime := time.Now()
 		events.EmitPostStart(nb.state.PoetProofRef[:])
 
-		proof, proofMetadata, err := nb.postSetupProvider.GenerateProof(ctx, nb.state.PoetProofRef[:], proving.WithPowCreator(nb.nodeID.Bytes()))
+		proof, proofMetadata, err := nb.postSetupProvider.GenerateProof(publishCtx, nb.state.PoetProofRef[:], proving.WithPowCreator(nb.nodeID.Bytes()))
 		if err != nil {
 			events.EmitPostFailure()
 			return nil, 0, fmt.Errorf("failed to generate Post: %w", err)
@@ -278,7 +282,7 @@ func (nb *NIPostBuilder) BuildNIPost(ctx context.Context, challenge *types.NIPos
 			return nil, 0, fmt.Errorf("failed to get commitment ATX: %w", err)
 		}
 		if err := nb.validator.Post(
-			ctx,
+			publishCtx,
 			challenge.PublishEpoch,
 			nb.nodeID,
 			commitmentAtxId,