I've gotten about half a dozen e-visas from the official site and that has never happened to me - it always prints exactly what I typed on the application.
The one between the two main checkpoints (and next to Visa on Arrival) is no longer being used for 70+ and First/Business Class - those categories now go to the right side of the regular immigration areas, following signs that say something like "Thai Passport & Priority".
Since you're on a retirement extension, there's no need to go get anything cancelled - immigration at Chamchuri will do that when they put the LTR in your passport. Congratulations!