I think my standard recommendation fits everybody even without knowing the skill level of the guitarists:  start at the beginning.

Start with the Fundamentals courses. If at first they are too easy, good on you!  Progressing through the lessons will be a nice refresher but ultimately you'll start running into new stuff and/or teaching of skills you don't have.

If it all is a breeze then the time spend with Fundamentals won't be much and then you can charge into the different genre courses or the more specific technique lessons.  Meanwhile, there's a catalog of song lessons to go through.  IMO, study/practice sessions should always allot time for learning songs.

Good luck, have fun.

john