Jasswiss, it's entirely possible your Thomas Reynolds is a relation of my man, although I'm not able to help much on that score as I haven't been able to pin down any hard facts on 'my' Thos. Reynolds yet, I'm afraid!
Nannyj, thank you for digging up that baptism! As you suggest, my Thomas may have been born a few years before. You mention KELDON Hall, so it does sound as if Kelvedon was often spelled (and probably pronounced) Keldon. I see Stondon Massey is not all that far from Kelvedon Hatch, and the evidence does seem to give a good case for my Thomas being born here rather than at the Kelvedon between Chelmsford and Colchester. It's entirely possible his parents were servants at, or tenants of, Kelvedon Hall, and would certainly explain how he came to be a coachman in later years. At present I'm experiencing some problems with my computer (hence the delay in replying to your post, Jasswiss) so I can't access my family tree program to check facts until it's been reloaded, but the info you have dug up sounds promising. As soon as I have had the bugs in my computer ironed out, I will do some more in-depth digging.