PS -- personally not a fan of agents -- but the best advise is always from your local immigration officer. Discuss with them -- establish rapport -- the process itself is easy if you have the deposits -- no need to waste money on agent.
I didn't notice if your monthly 130K deposits were into a local Thai bank -- if so Monthly deposits are cool. if not -- monthly allotments from your retirement or pension are cool -- the bank will provide the statements annually.
best to go to "your" immigration office and ask -- every office could interpret any situation differently -- sit down with an immigration officer. I am a big fan of face to face communication. Another option is to check with an immigration visa service in your area. If the change is complicated it may be worth their fees to make it happen. I recently changed from a retirement visa to a spouse visa and the Udon Thani office we as very helpful. Good Luck and best wishes on your transition.
