With the changes committed under SERVER-91195, we're expecting users to be able to remediate SERVER-91194 by calling collMod with the timeseriesBucketsMayHaveMixedSchemaData option set. This will ensure cluster-wide consistency of the timeseriesBucketsMayHaveMixedSchemaData time-series collection option.

In order to ensure that cluster-wide consistency is respected, such parameter must never be changed only at replica set level (shard level). There is one code snippet violating this condition during index build: when it is locally detected that there are no mixed schema buckets, the flag is locally unset. This can generate mismatch among different shards and can affect query planning, potentially leading to query incorrectness.