There's a question that has been asked several times in the shop guides thread that I don't have an answer to:

If a GA user's shops/items are above the non-GA limit, what happens to the extra shops/items once the user's GA expires? What will be accessible?

I want to test this, but my GA expires next month. So, I would much rather get an answer faster. If anyone has information regarding the question above, please let me know so I can update the guide!

I don't think anything happens to them. I filled a gallery with 6,000 items from the free gold account and now that I don't have a GA, my gallery's items are listed as 6,000/4,000 and still where I left them. I'm assuming that if I take an item out I won't be able to put it back in because of the fact I'm 2,000 items over the limit.

- That's what I'm assuming too. Thank you for the information! ^^

You're welcome :)