Yes - simultaneous departures from opposite ends of the same platform at New Street are permitted, even if it's confusing for the passenger.Yet both departing New Street at the same time from the same platform by the looks of it albeit in different directions at 15:21. Can the routes be set and called at the same time?
http://www.realtimetrains.co.uk/search/advanced/BHM/2019/05/22/1521