Ooh, difficult situation.
I am not saying don't change but I don't *think* you can be at 2 schools at the same time. Records, communication, differing techniques.... a minefield, nevermind the CAA rules. Far more knowledgeable and experienced folk than I will be able to give the technical answers but my two pennies worth -
Pick a school and stick with it, unless real issues with the training.
Pick an aircraft and stick with that. Bear in mind that there is much need to build up muscle memory in the early days (and indeed later days during training). The differences in cockpit, of the vital numbers, handling (eg, ground effect!) etc are another hurdle you could do without at this stage. Leaving aside the obvs room for error, it's just a capacity thing.
You get on with your instructor and like his style of teaching and he is getting the best out of you (vital) but, yes, you may find another instructor as good., you may well enjoy another ac, benefit from being closer and having more availability but, for me, Iogically (as I said, leaving aside the rules about ATOs etc), you need to choose and stick with it, at least for a good while..
Ask yourself few questions about why your current school have limited availability and whether this will improve. My school has quite a few students very close to qualifying, backlog due covid, which will free up instructor hours. Another school with limited ac but lots of hours available now will not look so good when the ac is/ are in for 50 hours check.
It is not an easy decision though, is it??
As you will have gathered I am extremely enthusiastic and want to crack on with my training but I secretly know that patience is a virtue AND more importantly even when not flying things have a way of working behind the scenes in your brain and you will improve before the next lesson.
In fact my very limited experience to date indicates that I should have 3.5 months off between lessons because I flew sooooo much better after the last lockdown than I had before it