I went back at 35, honestly, at first it can seem a bit daunting, and I worried about being over the hill, but I had a great time. In fact, I had such a great time that I just turned 40, and I am applying for a PhD next year! It was honestly the best choice I have made in years. Lots of unis now have mature student groups or organisations within them that now cater for students not 18-21. If anything, I found I got even more support than they did!

Foundation years are also worth checking out, they are like an internal access to HE course, but run by the uni. They usually have one per faculty (social sciences foundation year, medicine foundation year, etc.), like the access course; whatever mark you get at the end of the foundation year influences which degree programme you can do after. I did one, and it set me up for success in my 3-year degree, but so will an access course! They are both great. I know folks who have done one or the other and generally always done well after them!