The changes, due to commence in January, can be viewed on the website by clicking here which gives further links providing more details on individual routes
Christian Newsome has brought the information to my attention and comments that First are hitting back by offering express services between Norwich and Lowestoft missing out North Cove and Hales; exactly the same as AnglianBus 146.
He suggests the most interesting development is the re-routing and timetable change of the X22 which will now go via Carlton Village. This is a strange routing because First seem to be reintroducing their old L11 (Carlton Colville via Long Road) route again which saw buses running empty leading to its withdrawal. Time will tell.
Many thanks for the heads up Christian