Unfortunately, we don't know how things are processing at the DVLA - though it's not surprising to hear there's still a backlog of V5Cs to be sorted as the DVLA wasn't operating at full capacity for a significant part of 2020 due to Covid restrictions. I'm afraid it'll be a case of waiting until it comes back to you, though I'd call their customer services team and see if you can find out some more info about your application.