Personal prediction for the new vehicles:

Angel:
18 new buses on the 21 displaces 16 Streetdecks onto the 301 (as rumoured) + 2 older deckers withdrawn
10 Streetlites go to Washington to displace the Citaros
5 Streetlites stay at Percy Main withdrawing 83XX Versa's
1 Streetlite goes to Consett displacing an extra E200MMC to Riverside to withdraw an 83XX Versa

X66
4 new buses displaces 3x Supershuttle E200MMC plus 1x extra as above to Hexham for 684
4 x Versa's from Hexham to Riverside withdrawing last of the 83XX Versa

58
7 new buses on the 58 displacing 7 older deckers

25 x New Buses - X1, X10 and X21
4 new buses on X10 displaces 4 E400MMC's to Consett for X-Line circuit withdrawing 4 older deckers
13 new buses on X1 displaces 13 Streetdecks to the 56, 56 B9's spread to withdraw older deckers
8 new buses on the X21 displaces 2 for the 56, 3 for Washington for 14/50 + extra spare, 3 for Riverside as 21/X21 spares withdrawing older deckers

Total of 34 older deckers withdrawn accounting for all B7's, Gemini 1's, Dual Door E400's and Olympus's