@Derek *****
I think you've got your wires crossed. There is no requirement to leave the country and come back to 'renew' anything.
LOOK in your passport at your stamp, does it say "extension of stay permitted until" and have a date on it? If so you can apply for a NEW yearly extension by meeting the proof of funds and turning in the required documents at your immigration office for 1900baht.
IF you decide NOT to get another extension before you leave the country and the current one expires while you're outside thailand, you start ALL over, getting a 90 day Non-O visa (which you can do before you come back at the thai consulate in the country you're in) and then applying for a year extension