Hi, Tardelli!
I was in the same boat – my conditions also meant I couldn’t renew my Short-term Medical Driving Licence on-line and had to apply via form filling.
In total it took the DVLA eight and a half months to complete my application and no, you really can’t contact them about it any more. The email address vanished at the start of last year and the contact phone number disappeared at the end of July. When I did manage to take to someone in early June the bloke I spoke to had no idea how long the process was going to take (there was a shortage of Medical Assessors, plus the ones they had went on strike for a month) and I was told I just had to wait for the DVLA to either contact me or send me the new Licence.
Not really helpful as such, but at least you know you’ve not done anything wrong.