Can I change my extension of stay to married with a Thai before it expires?

So, you applied for your 1-year extension at the local immigration office, right?

Just making sure because many Non-OA visa holders mistake the second-year entry stamp with an actual extension. IF in that case, there would be a bit of a different story.

as long as you have a valid re-entry permit (so you get stamped back in ON this current extension when you return) and as long as you can get the documentation, etc together in the time you have from when you come back to when your current extension expires you'll be fine.

You're comin' back the 15 of Oct and your extension expires Nov 1 so once you get back you need to not screw around getting the documentation together and going to apply. It can totally work, IF you get your ducks in a row quickly upon your return here