diff --git a/CHANGELOG.md b/CHANGELOG.md
index 46985a4..3eba188 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,12 @@ Tags follow `v{opencode_version}[letter]` — bare tag for the first build on a
 
 ## Unreleased
 
+## v1.15.0b — 2026-05-15
+
+Rebuild of v1.15.0 with one fix — v1.15.0's `omos` variant landed at 3206 MB, 6 MB over the 3200 MB smoke threshold, so `smoke-omos` failed and `build-variant-omos` was skipped. opencode 1.15.0 grew slightly vs 1.14.50, leaving zero headroom on the existing threshold.
+
+- **Smoke threshold bump:** `omos` 3200 → 3300 MB, `omos-with-pi` 3400 → 3500 MB. Restores ~100 MB headroom for routine apt-get upgrade drift between releases. Documented inline in `scripts/smoke-test.sh`. No image-side changes — cache hits across the board, just a re-publish on the bumped threshold.
+
 ## v1.15.0 — 2026-05-15
 
 opencode 1.14.50 → 1.15.0 bump (upstream minor release).
diff --git a/scripts/smoke-test.sh b/scripts/smoke-test.sh
index e5ad8e8..899dda4 100755
--- a/scripts/smoke-test.sh
+++ b/scripts/smoke-test.sh
@@ -289,14 +289,16 @@ SIZE_BYTES=$(docker image inspect --format='{{.Size}}' "$IMAGE")
 SIZE_MB=$((SIZE_BYTES / 1024 / 1024))
 echo "  Uncompressed size: ${SIZE_MB} MB"
 
-# Thresholds (uncompressed): base 2500 MB, omos 3200 MB, with-pi adds ~150 MB.
+# Thresholds (uncompressed): base 2500 MB, omos 3300 MB, with-pi adds ~150 MB.
 # omos bumped 3000→3200 on v1.14.31c — mempalace-toolkit bake-in pushed the
+# baseline; bumped 3200→3300 on v1.15.0 — opencode 1.15.0 came in at
+# 3206 MB, leaving zero headroom for routine apt-get upgrade drift.
 # omos variant to ~3.1 GB. Functional smoke checks all pass; this is a
 # guardrail, not a performance limit.
 THRESHOLD=2500
-[ "$VARIANT" = "omos" ] && THRESHOLD=3200
+[ "$VARIANT" = "omos" ] && THRESHOLD=3300
 [ "$VARIANT" = "with-pi" ] && THRESHOLD=2700
-[ "$VARIANT" = "omos-with-pi" ] && THRESHOLD=3400
+[ "$VARIANT" = "omos-with-pi" ] && THRESHOLD=3500
 if [ "$SIZE_MB" -gt "$THRESHOLD" ]; then
   fail "image size ${SIZE_MB} MB exceeds threshold ${THRESHOLD} MB for variant=$VARIANT"
 else