The following bug has been logged on the website:
Bug reference: 11032
Logged by: Sergiy Zuban
Email address: s(dot)zuban(at)gmail(dot)com
PostgreSQL version: 9.3.5
Operating system: Linux
Description:
After upgrade from 9.3.4 to 9.3.5 pg_last_xact_replay_timestamp() returns
outdated timestamp.
It stopped working properly after commit
d19bd29f07aef9e508ff047d128a4046cc8bc1e2
COMMIT PREPARED should update transaction timestamp, but it doesn't seem to
happen.