I don't think waiting is necessary, especially if you (or anyone else) is feeling the itch to post something. I reckon it'll likely take us a few days to progress through the meeting anyway—dialogue, chances to react, etc. And again, even if one misses the first meeting, there will be opportunities to jump in later. Someone comes in right after the meeting is over? Maybe they run into one of us on the way out of the library. Someone joins in a few months? Maybe they sneeze fire and singe off someone's eyebrows. Excellent conversation starter.
...Anyway, we can be flexible. What I don't want to do is intentionally hold back the creativity of those of y'all wanting to write right now. I think this is fair.