Major Description
If the client species SCAN_AT_SNAPSHOT, and then tries to read from a replica, it's possible the replica won't have recent enough data to service the scan, or the replica may have some operations that are "stuck" started but not yet committed because the leader recently crashed. In this case, it responds with 'Timed out: could not wait for desired snapshot timestamp to be consistent: Timed out waiting for all transactions with ts < P: 1457574158715836 usec, L: 0 to commit'. However, it's possible (likely, even) that another replica does have this operation committed. The client doesn't handle this error at the moment and instead propagates it to the caller even if it could otherwise failover.