I just asked this question asking why I couldn't see the edit link anymore to make suggested edits (I do not have 2000+ reputation yet to make edits on my own). It turns out I should have looked around Meta some more: https://meta.stackoverflow.com/search?q=suggested+edit+queue+full
The answer I got said that people with 2000+ reputation can see how many items are still in the suggested edit queue, but as I have not got that far yet I obviously cannot see that and therefore had no knowledge of this.
My suggestion is to tell us with less reputation that edits are unavailable at the moment. I'm not expecting the same thing as those who can see the suggested edit queue, but at least some visual indication/message on the Review page - it would save us from having to come asking on Meta all the time.