To update, I heard from both @MOGUL and @Garfield yesterday, and my VIP status issue has been resolved.
Turns out that their charming AccuraBot was hosting an AI revolt, and was closing tickets that should not have been closed.
I suspect, but don't know, that the VIP status issue was due to the A/S platform not recognising previously-redeemed points, only remaining points.
For example, if you had earned 5000 points on the IRM platform, and redeemed 2500 of them on gift cards or orders or whatever, you had a remaining balance of 2500 points.
It's possible, or even probable, that the A/S platform only recognised the 2500 remaining points, and awarded you a corresponding tier / level for 2500 points, rather than for your 5000 EARNED points.
This is only speculation on my part, but I would suggest that anybody concerned about their VIP status checks that their tier / level is correct.
When you reach the higher tiers, it makes a difference in how many reward points you earn per £ GBP spent.
Big thanks to the guys for sorting mine!
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