crosscity
Member
I'm not convinced there are 5 323 diagrams, unless a 323 was substituted for a failed 730.1723, 1753, 1823, 1853 (all Bromsgrove) and 1643, 1715 (Redditch) departures south from New Street are reliably class 730s. Bromsgrove is a 3hr diagram cycle, Redditch is 2.5hrs; you can work out all the other services from that. 6 diagrams, all should be pairs so 12 units.
The other 5 cross city diagrams (2 Bromsgrove, 3 Redditch) are (should be) class 323s. Typically two of these (1 of each route) will be a pair, the other 3 will be single (so 7 units total)
There have been occasions when a 323 has been replaced with another 323 on the same diagram.
The four 323 diagrams are 3 Redditch and 1 Bromsgrove.