Updated the wiki with a no - no for Curaçao. Avoid traveling outbound on Sundays by all means, if you can. Check-in at the SkyPriority desk 2h before scheduled departure and I was still in line for security checks at the time of gate closure. KL station manager and local director both came to the security check area to ask airport staff to open an additional line for the approx 30 (!) remaining KL pax, to avoid delays or leaving anyone behind at the last flight of the day.
Traveling regularly from CUR, I can say it's not an exception at all. No elite benefits or whatsoever there, just make sure when traveling on Sundays you arrive well in advance. There is no priority security line or immigration, doesn't really matter whether you've paid 5000 € for a J ticket or for 250 €, hotel included, on an all-inclusive vacation.