You give upgrade instructions that can't be found [resolved]

[Pilate]

[Old Bruce]

The application menu in this case is Affinity Designer so you are looking in the right place. I think this is like my setup, Designer was purchased from the Mac App store so there won't be an Update item. My App Store (somewhere in Canada) showed the update to be available this morning local time (late afternoon in the UK). Your area may be waiting on the region's Mac App Store. You may find that you have to sign out and then in again at the Mac App store due to OS oddities.

For Publisher I have the update line in the Application Menu. That is because I purchased it from the Serif/Affinity web store.

[Pilate]

Actually, Publisher ran through the typical process of notification and updating.   Photo and Designer show up in the App Store but as you've said, maybe it's a time zone issue at this point.

 

[R C-R]

5 hours ago, Pilate said:

Photo and Designer show up in the App Store...

And in your screenshot, each of them has an "Open" button. That means you purchased them from the Mac App Store -- otherwise, like for Publisher in your screenshot, you would see a price button instead of the Open one.

This is why there is no "Check for Updates" button in your copies of AD & AP -- you did not purchase them from the Affinity Store.