Can I travel to Singapore with an expiring non-immigrant visa and a new re-entry permit?

I have a non-immigrant visa based on marriage to a Thai (husband). I recently applied for a 1 year extension (as I do every year) and must report back on 24th July to get my new stamps. My current visa (and thus multiple re-entry permit) expires on 21st July so there's basically a 3 day window between expiry and picking up my new stamps. During this period (21-22 July) I need to travel to Singapore for work. Am I correct in thinking, I can do this but just need a new single re-entry permit to cover this? I plan to get it at the airport tomorrow before leaving.