It would seem I have lost my 90 day extension receipt that was supposed to be in my passport. Anyone know what I need to do before I return to Immigration to further extend?

I assume you are writing about your 90 day report receipt. They are not extensions.

The immigration office where you do your reports should have a record of your last report. If not you will have to pay a 2000 baht fine.

Cool - thanks Ubonjoe. Not sure if you know, but my last report was done at Lat Prow - is that still acting as substitute for Chaing Wattana or still open as an Immigration Office in its own right?

You can still do 90 day reports at Lad Phrao, Since that is where you did your last report that would be the best place to go.

For anything else you have to Chaeng Wattana.

Thanks a lot for your help