Radim Vansa The second assertion is asserting against the transaction-start-time from the Session, not against the Session itself...

The Session's current transaction-start-timestamp and its current CacheTransactionContext are 1:1 ideas. The assertions should be consistent. The difference, and what I am trying to figure out, is whether you are expecting the Session to call RegionFactory#startTransaction every time we recognize a new physical transaction boundary, or whether the CacheTransactionContext returned from RegionFactory#startTransaction will itself be sensitive to these boundaries.