Contact default bridge operators and ask them to upgrade obfsproxy package
From ACT meeting logs:
16:06:42 dcf1: How about starting with the Tor Browser default bridges?
16:06:50 meskio: +1
16:22:34 meskio: ggus: do you want to contact the default bridges about the obfs4 upgrade? or should I do it? (I guess I can find their contact somewhere in the wiki)
logs
Default bridges contact info: https://gitlab.torproject.org/tpo/anti-censorship/team/-/wikis/Default-Bridges