I'd expect they will spread around the 'DLAs' to replace the Lowlanders at Durham first, before getting rid of the more tired DAF ALX400s too.
In other news, 1405 should enter service at Stockton today, was down to be on X66/7 when I left. Had a quick look at it and it's not got any branding yet.
RE: Arriva North East: Latest News & Discussion - December 2015