Today, 17:05
I've had this happen too. But if you try to start the sim after the update is available and before the Store has picked it up, the sim should redirect you to the store to get the update.
https://forums.flightsimulator.com/t/366571
Vote for this bug on the official forum, then file a Zendesk ticket. At last check, this glaring issue was still down at #21 on the bugs list. More votes and more ZD tickets will bring it up on the priority list.