I am looking as well. I emailed the ticket staff and they said on Feb 3 there will be some upgrades thrown in for sale, using the ones that people cancelled. The upgrades require you to already have a standard badge.
Lt. Amstrong (FMAB) - Otakon 2018
Ryu (and Ken, Street Fighter) - Otakon 2018
Hiccup (HTTYD: The Hidden World) - Otakon 2018
Powerline/Max (The Goofy Movie) - Otakon 2018
U.A. Student (My Hero Academia) - Otakon 2018 (Backup cosplay)
Southern Maryland Cosplayers Group
(Anyone can join)