I'm pretty sure if you're careful, you can undo early tnr. Some will likely come undone without any help. Depends on how good you tnrd it. TNR is definitely something I did out of impatience.
Use like one or two teaspoons of salt to a regular sized spray bottle. Some will come undone. You will get uneven length dreads as they kinda do their own thing. Don't do too much to them though. Just remember, it's a long process. It can take two or more years to look really good.
To be honest, I might not be one to give advice, but don't use wax. I started with wax and ended up getting it out thankfully because of this site. After the wax was out, my hair came undone but not completely, and it just started doing the rest with time. I wanted to cut my hair so many times early on, because I didn't see progress. My last hair cut was a fade, so the sides and back didn't do much at first. I got impatient and twist and ripped the rest to even out the progress so to speak? I spray salt water on my hair every day, 2 or three times. I put tea tree oil in it, eucalyptus oil, and lime oil. Smells good, and helps keep dreads clean. Natural water is best. Every time I swim in a mountain runoff, I see more progress than tap water. Best advice is this; stop looking in mirrors, and stop worrying. Well, if your dreads start combining, you might want to separate them, but don't use full force.
I hope that covers it.