... I DM'd the org via Twitter a couple weeks ago, and got the reply that they've "been too busy"
Some organisers see the ride as 'the thing' and everything else surrounding it (and especially after the event) as taking much lower priority. It's rather difficult to argue with that philosophy but it does mean that sometimes results are very delayed.
About 3 months ago I completed a Calendar Event within the required time. My brevet card was checked and instantly validated on the day. However, the ride has yet to appear on my AUK member's results page. Is this something the event organiser takes care of or should I have notified someone at AUK?
There's a chain of events but in the first instance it's up to the organiser to notify AUK that you finished their ride.
* If the ride hasn't appeared in the 'Event Results Sheets' page - then that is just the organiser taking his time. Eventually, AUK would probably take notice and prod with a pointed stick - though if it is last season, things get a bit more complicated.
* If there are riders listed on the 'Event Results Sheet' and you are included, then the ride should also appear on your 'Individual Rides List'.
If it doesn't (most unlikely) that would be a system error and AUK's Recorder is the person to notify - make sure you mention your membership number and the event number if you know it, or the date and location/distance.
* If there are riders listed on the Results Sheet and you are not in that list, then you would have to contact the organiser, because that means he has finished with the event but hasn't passed your name or number along to AUK.