Sorry for the late notice - although I'm sure many of you already knew about this, this is the first I have seen dates around this.
If you would like to host a DevRoom (ie, a content track) at the upcoming FOSDEM, the deadline for applying is October 31st.
Details are here: https://fosdem.org/2021/news/2020-10-26-devroom-cfp/
Key dates:
31 October deadline for developer room proposals
10 November accepted developer rooms announced
15 November (or earlier) developer rooms issue Calls for Participation
31 December (or earlier) developer rooms publish complete schedules
All deadlines are at 23:59 UTC.