From British Bus Publishing: -
(The Van Hool Astromegas don't appear on the official Stagecoach 'New Orders press release, can anyone shed any light?)

STAGECOACH ORDERS 2015 – 2016.

10431 – 10487 Enviro 400 Euro 6 Enviro 400MMC
10431 – 10442 for Oxford.
10443 – 10451 for Wigan.
Rest unallocated.

12364 – 12389 Enviro 400H Enviro 400
All for London.
13041 – 13080 Volvo B5LH Enviro 400MMC
All for London.
15211 – 15220 Scania N230UD Enviro 400
For Fenstanton (guided busway).
15221 – 15260 Scania N230UD Enviro 400
15221 – 15225 for Lillyhall.
15226 – 15249 for Chorley.
15250 for Torquay.
15251 – 15260 for Exeter.
15261 – 15290 Scania N230UD Enviro 400MMC
No allocations shown.
21301 – 21310 Volvo B8R Wrightbus Eclipse
For Fenstanton.
26001 – 26033 Enviro 200 Enviro 200MMC
26001 – 26019 for Cowdenbeath.
26020 – 26023 for Barnsley.
26024 – 26033 for Rawmarsh.
27211 – 27299 Enviro 300 Enviro 300
27211- 27225 for Glasgow.
27226 for South West.
27227 – 27228 for Glasgow.
27229 – 27237 for Wigan.
27238 – 27254 for Stockton.
27255 – 27272 for Rock Ferry.
27273 – 27299 no allocations shown.
28721 – 28748 Scania N3230UB Enviro 300
28721 – 28741 for Cwmbran.
28742 – 28746 for Banbury.
28747 – 28748 for Lillyhall.
36601 – 36608 Enviro 200 Enviro 200MMC
For Romford.
37301 – 37327 Enviro 200 Enviro 200
37301 – 37319 for South Shields.
37320 – 37326 for Gloucester.
37327 for Hastings.
37401 – 37423 Enviro 200 Enviro 200MMC
No allocations shown.
47941 - 47966 Optare Solo M920SR Optare
All for Carlisle.
47967 – 47980 Optare Solo M990SR Optare
All for Leamington Spa.
48001 – 48020 Optare Solo M920SL Optare
48001 – 48002 for Carlisle.
48003 – 48020 for Exeter.
48021 – 48025 Optare Solo M990SL Optare
All for King’s Lynn.
53801 – 53812 Volvo B8R Plaxton Elite i
All for Aberhill.
54241 – 54262 Volvo B11R Plaxton Elite i
54241 – 54257 for Buchan / Peterhead.
54258 – 54262 for Glasgow.
54263 – 54276 Volvo B11R Plaxton Elite i
All for Rugby.
56028 – 56050 Van Hool Astromega TDX27 Euro6 Van Hool
All for Rugby.