Late to the party... I have one, bought it as a replacement for my '65 6119 *and* '03 6120. To me, it sits right in between the two. The combo of the electrotone body and Filters (not to mention the looks!) was what did it for me. I also prefer a mud-switch to tone knob, and like the ON/OFF switch on my '65. The RW Tenny has both. Got it REAL cheap using GC coupons, tax-free store, and discount bux.
The only thing I don't like about it is the lack of zero fret and the headstock is a bit ordinary looking to me. Would have been nice to have some sort of metal plate.
Mine is number 126 made in January 2021 so your hypothesis may be correct.Before I bought mine, I did an "informal" survey of available serial numbers (GC/MF, Sweetwater, Reverb, etc.) and found two "batches" early on (or maybe one long one), followed by one more batch in April of the following year. I don't know how many guitars are in a "Limited Edition" Gretsch run (especially with the "pro" level models), but I guess there could be as little as 150 of these floating around, or maybe as many as 300. Who knows, just my uneducated, circumstantial evidence, based opinion...!
Yeah, most of the S/N's I found a were from December '20 / January '21. Some were from a later batch in April '21 (which is the batch mine is from). I don't have my notes anymore, but there may have even been a lone straggler from November '20 (I can't remember).
Who knows how many were actually made, but considering its rare to even find *any* pro-line model in a store (at least near me), it can't be all that many of them.