I don't use a VPN and I don't have a dynamic IP address. I'm on Windows PC, using Pale Moon, Chrome, or Firefox. Same problem on my work and home PCs. Happens even with brand new bookmarks (like the one I set for the new Poser 12 forum).

I get logged out in the middle of shopping. The only reason I notice is that I see a product I know I bought, and the little shopping cart icon isn't grayed out.

This wasn't a problem until recently. You'd stay logged in basically forever. I can see them wanting to shorten that, but this is ridiculous.