VS Heathrow Clubhouse Question

Have an SFO-LHR RT coming up on VS, and will be Platinum when I land at LHR on the outbound. I'd like to use the VS Clubhouse on my return but it's 4 days later and the MQMs from the outbound trip might not have posted then. What's the best way to let VS know I'm PM so I can access the Clubhouse?

I'm in Premium, not Upper Class, so won't get it from my ticket