Hi, I'm supposed to do my 3 monthly trip out if Thailand for my 1 year visa. I'm going to leave a day after it needs me to leave. Will I have any problems at immigration. Also, is burma still allowed by land. I've done this route for the last year now.

If leaving by a land border you will be fined 500 Baht for 1 day overstay along with the relevant stamps in your passport (1 day is only "free" at airports).

 

Not sure about the Burmah stuff.

I assume you mean your current 90 day entry is ending and you want to leave and re-enter to get a new 90 day entry.

You will need to pay a fine of 500 baht for a one day overstay if you leave the day after your current permit to stay ends.

If you still have a valid visa for re-entry you can do the crossing at any of them to Myanmar.