Anyone who posts videos or sound file of pieces (including technical exercises) they are playing in the Classical Guitar Corner Academy (CGCA), either in their Progress Journal or the Student Showcase, will get feedback. The feedback comes from other members, either as encouragement or, from the more experienced players, helpful advice. Very often, the Community Manager, Dave Belcher (who is also one of the tutors), will comment. Sometimes one of the other tutors (Kevin Gallagher and Connie Sheu) chip in with suggestions.
To get more formal feedback from Simon Powis or one of the three tutors, members can: (a) participate in the Member Challenges held every couple of months [each focused on a particular facet--this month is 2- or 3-octave arpeggios; progress videos must be posted every week]; and/or (b) book a slot in Office Hours in which one of the tutors will offer advice on any element of playing, or a piece, or discuss questions, that each member elects--slots are available most weeks over a reasonable range of time zones; and/or (c) opt to play at a live member event held once per month--detailed feedback will be given by Simon; and/or (d) participate in the formal courses, covering theory, technical work, and repertoire, which are formally evaluated through submitted videos; this is moving to an 8-level grade system in September 2018; and/or (e) participate in an annual summer school near Boston, USA.
I participate in (a)--(d) myself. Maybe I will try to addend the summer school in 2019, but I live 12,000 km away. There is quite detailed information about all of this on the CGCA website, and you can join month-by-month to try it out before committing to an annual subscription. You have to be an annual member to be involved in (b) and (d), also depending on the membership tier. Anyone, member or not, can attend the summer school.