I am at the end of year 12 at the moment and I also had to do 4 a levels at the start. I chose to do EPQ alongside it and I performed well in it while achieving predicted grades A*A*AA in my A Level subjects. From my experience it is definitely possible to perform well in it but you do need a good amount of time management skills. I was also able to do some work experience alongside this however, I am looking to do engineering so virtual work experience worked well for me and I am aware that for medicine this is not the case.