Find that brochure
They have a brochure at the DMV, actually it's more like a tri-fold or bi-fold pamphlet (don't remember anymore) and it says "Acceptable Legal Presence Documents" and on that list it will say I-797 and it doesn't say it has to be I-797A. Try telling the DMV person that all you have right now is the I-797N but you will receive the I-797A soon, you're just waiting for it at the moment and you don't want your license to expire. Can he/she help you somehow? and then promise him/her that you will submit the I-797A as soon as you receive it. The person might be more considerate, if that doesn't work, go to another DMV. Don't worry about trying to renew as many times and at as many locations as you need to. They can't turn you down for trying several times, there's no limit, so just keep finding another DMV office until you get a good guy. Remember, this is what I did too (thanks to my driving instructor who drove me around) and this is how I got my license back in 1999. I haven't had a problem renewing it since then.
