I wouldn’t worry too much, some gp’s take ages to reply to the dvla
i’m currently waiting for mine to come back but due to having a one off fit 17 years ago (side effect to a school jab) they’ve had to write to my gp just to confirm it all.
you should have a letter from the dvla saying that’s what they’re doing
might be worth chasing it up with your gp, although i’m not sure if they’ll give out that info