Unless you have re-entry permit on your visa, when you leave and come back it would automatically cancel your non-o anyway as you wouldnt have the permission to re-enter the country on that visa. Therefore, they would only give you a tourist visa anyway so you dont need to worry. If you have a re-entry permit then as above, speak with an agent

@Brandon ***********

i literally converted to a Non-O last month using the monthly deposit method. If you can not get income verification from the embassy which UK embassy do not provide now, then some immigration offices allow you to use bank statements, a contract confirming your income and sometimes they may ask for a letter of confirmation from your employer or wherever your income is from. I used bank statements from my UK bank, statements from my wives Thai bank showing the deposits and my contract. I have been sending over 100k a month though so maybe that helped too but you definitely can convert to Non-O without the 400k deposit