They mentioned that there'll be multiple campaigns - I believe the first one was some sort of RoE/Ambuscade counter across all worlds, that'll be tracked on the website. Once the count hits 100%, each day you get a free Abdhaljs Seal buff when you enter Ambuscade.
(That was my very poor understanding of it)
You got some of the main points, but the way these cross-server "challenges" are going to work is...
1) Players participate in whatever the target content is to earn points towards some goal.
2) If players across all servers reach 100% of the goal, then an additional campaign will be added to the
following month's adventurer campaigns. Fujito mentioned the additional campaigns will all be campaigns we've not seen before (double Segs/Muffins/Exemplar Points, anyone!?).
3) There will also be individual points/rewards that can be earned regardless of whether or not the all-server goal is met.
So the November challenge is for Ambu/RoE, and if players across all servers reach 100% of whatever the goal is, then a brand new Ambu point campaign will take place in December.
For this special Ambu point campaign specifically, they mentioned that
players will receive an Abdhaljs Seal effect once per day for each difficulty level of Ambuscade. The wording is vague, so one of the panelists/the voice actress followed up by asking, "By 'difficulty' do you just mean Regular/Intense ambu, or literally for each difficulty from VE to VD?" It looks like someone nods off-screen and confirms the latter, meaning you could get the effect of a Seal (without it cluttering up your inventory!) 5x a day (VE, E, N, D, VD) during the campaign period.
Now, I didn't actually
hear Fujito confirm that, but again, it looked like someone nods off-screen. So it may change, but that's what I gathered from the exchange. Still, the guy who followed up/the voice actress were both quite excited about the possibilities for earning mats from Ambu. And it would indeed be a brand new campaign we've never seen before. But Fujito did reiterate that "Players have to earn it! It's not guaranteed to be implemented yet, y'all!"