In November 2016 there was a discussion on the tor-team list about adding some new default obfs4 bridges (Subject: Coordinating to run high capacity obfs4 bridges). The thread turned into a discussion about the same entity running both bridges and exits, and didn't go anywhere.
We haven't added any new obfs4 bridges, or changed the port number of any existing bridges, since January 2017 (Tor Browser 6.5 and 7.0a1). I suspect that the 20 existing default bridges are still under high load and we could stand to have some more bridges to help share it. Are we still interested in adding new obfs4 bridges? If so, do we have any leads on who could run them?