Is it too late to switch subjectsWatch
Anecdotally at my school it wasn't uncommon for people to swap from HL Maths to SL (or SL to Maths Studies, which no longer exists), although usually it happened at the start or end of the academic year (i.e. just after the start of year 12, at the end of year 12, or just at the start of year 13) although I suppose a few people might have swapped in the middle. However this was over 10 years ago and the format of a lot of assessment has changed in IB so, I can't guarantee it's indicative of anything. In terms of swapping to English specifically one thing to note is that you will probably have more literary texts to study in HL so you might need to catch up reading some of the things you missed so far, which may end up being quite a lot of reading to do!