At EclipseCon, Tuesday and Wednesday are "BoF Nights," with a mix of pre-scheduled and onsite-organized Birds of a Feather (BoF) sessions during the evening.
If you would like to organize a BoF after you arrive at the conference, just visit the BoF Board by registration and sign up. The BoF Board is also the place to see what BoFs have been organized so that you can choose which ones to attend.
Note that all the slots for pre-scheduled BoFs have been filled, but there are still many openings available for those organized on site.
