I had been on the WL for an upgrade to J for a few months and even extended it to T-48 but it never cleared (expertflyer was showing reasonable I availability). At T-4 there was availability for straight J redemption on the CX website but when I requested an instant upgrade for myself and my partner at check-in a bit later we were told nothing was available but to check again later....

Once I got to the lounge I asked again and was informed there was a memo on my booking that it was my 5 year anniversary and this milestone had a higher priority than any attempt for a mileage upgrade and I would need to wait until closer to boarding to find out. Luck have it when we got to the gate we were both upgraded to J (even though she was on a separate booking).

This upgrade was approximately 1 week after my 5 year anniversary date.