diff --git a/app/services/pending_namer.ts b/app/services/pending_namer.ts
index 8840404..046f622 100644
--- a/app/services/pending_namer.ts
+++ b/app/services/pending_namer.ts
@@ -9,6 +9,7 @@ import { XoverClient } from '#lib/nntp/index'
 import { RangeIndexer, type ReleaseChunk } from '#lib/edge/index'
 import { identityKey } from '#lib/release/keys'
 import BatchStore from '#services/batch_store'
+import ChunkPartitions from '#services/chunk_partitions'
 import Corpus from '#services/corpus'
 import RuleSets from '#services/rule_sets'
 import { PENDING } from '#services/pending_ladder'
@@ -135,6 +136,8 @@ export class PendingNamer {
     const candidates = batch.candidates
       .filter((c) => c.releaseKey === found.key)
       .map((c) => ({ ...c, upload: found.upload }))
+    // The chunk's month partition, as the batch store makes sure of before its writes.
+    await ChunkPartitions.ensure()
     await db.transaction(async (trx) => {
       const blockId = await BatchStore.blockOf(trx, range)
       await BatchStore.writeReleases(