I’d say Imperial agents is too far away, and yea, that may be true, although Adepticon is on March 24ish so realistically after 2 more weeks of reveals after tomorrow (that could have a week breaking them up) that is basically on the date
plus GW love to show off 2 codexes for each event, but one having already had models revealed,
necrons (already had a model shown) and admech at one event, followed by Dark angels (which already had models revealed and the Kroot box at the next, most likely, show off rest of Kroot and then reveal 1 codex with 1 model, maybe at a stretch reveal the other out of custodes, orks and chaos but I doubt 3 codex related reveals at one event