First have released the new timetable for the 9, which will apply from 5th July. Only a few morning journeys have been retimed.
Not quite bus related, but you may have noticed that the trains from Brentwood station are now operated by TfL Rail rather then Abellio Greater Anglia. This is the first step of the transition to Crossrail.
For now, it means lower rail fares for some journeys as train travel from Greater London to Brentwood now uses the same fare scale as the tube, rather than a premium being charged for what was a National Rail service.
The line is still technically part of National Rail however, meaning a through rail ticket to or from any other railway station in the UK is still available to/from Brentwood. A paper rail ticket is still needed in order to buy a Brentwood/Shenfield Plusbus ticket.