Don’t know, there was the “brain damaged” Hazeltine mode even in V6.     I suspect there were a lot of random things kicking around that got hooked up after the initial model 33 and 37 ttys.

I’ve found several early pictures, one of Ritchie, and another of Thompson (though Ritchie is in the background) sitting with what appear to be Tektronix 4014s.