Wednesday is traditionally the best day of the week. However, you are dealing with a unionized government entity. Your needs are not a priority. I would recommend going with a younger family member that can wait in line from 03:30 - 04:00 until they open at 08:00 while you sleep in the car. I was there from 05:00 until 13:00. Good luck.
You can also try to renew your driving license online if you are not required or if you don't want to change your picture. I did mine online and it came home. You do need to pay with credit card and Motor Vehicle does charge $1 to $3 convenience fee but it is worth for avoiding long lines and waste of entire day.
No they not first come first serve basis
I don't believe they are doing any special hours or days for senior citizens.
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