Changes have been registered
Services variations are: 1, 3 (Darlo), 4, 5 (Darlington & Stockton), 6, 7 (Darlington & Stockton), 8/8A, 9/10, 13A/13B, 17/17A, 19, 22, 23, 24, 28/28A, 29, 43, 48, 49, 56, 62, 63, 64 (Durham), 81, ED3, P1/P2, X3, X22, X26/X27, X46, X66, X75/X76
Services cancelled (that I can see): 6 (Cockfield - Barnard Castle section), 12, 86, X1 (looks to be no replacement for Tow Law to Stanhope extension), X21
I'm sure someone is able to provide greater insight on these
Arriva North East: Upcoming Service Changes