I did have a conversation with customer support and while they didn't specifically inform me of the Avengers box availability, they were very pleasant and helpful. I ended up turning the auto-renew on my current sub off and placing a new order for the Civil War box so I could prder the Avengers box (which we all knew I would have to do). While I did this, I went through all of the sizing options for all the past boxes to find out availability for everything. Obviously, this won't be accurate for long, but if anyone wanted to get a past box, now is the time to do it while you can still edit your auto-renew option for the Civil War box.
Anyway, here is the sizes that were currently available (as of 3.28.2016, 9:30am)
Avengers - M, L, XL
Ant-Man - M, L, XL, XXXL
Secret Wars - XS, M, L, XL, XXL, XXXL
Villains - SOLD OUT
Guardians of the Galaxy - XS, S, M, L, XL, XXL, XXXL
Deadpool - XS, S
Hope someone find this useful.
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