I’m renewing my marriage visa in early November.
Right after that, I’m applying for a re-entry permit.
Can I leave as long as 6 months?
TLDR : Answer Summary
You can leave Thailand for up to 6 months after renewing your marriage visa and obtaining a re-entry permit, as long as you return before your extension of stay and re-entry permit expire. It is advisable to get a new yearly extension at the time of your visa renewal.