I did the Epic beginners and went straight onto Epic 3. I would say you can start the advent (or indeed Epic Endgame that starts next week), as you can start on lower weights/fewer reps and build up from there. I went up from 3-6kg on epic 3 from day 1 to 50. The exercises don't change, the difficulty increases when you increase the weight.
(or at least that's my take on it).
I liked advent as it's only 15-20 minutes a day, so easy to fit in, but some of them made me ache afterwards!