Originally Posted by TMC
Supposedly, the 7th season of the show was intended to be the last so much of the cast had made plans for other projects. At the last minute, it was decided to go on for one more season so that's why David L. Lander is a regular but Michael McKean (Lenny) only made a few guest appearances. Betty Garrett
was doing a Broadway show so they wrote her character had run off and left Laverne's dad. Apparently the episode where Laverne finds the note that Shirley has left was supposed to be the one dealing with Edna leaving Frank but when Williams left they rewrote it to deal with the more pressing void. The Edna-Frank situation was ignored until the second half of the season.
If Betty had moved on, why did they have Frank and Edna separate? Frank could have talked to Edna over the phone or gotten letters from her in those episodes; she just would have been invisible like Sara the telephone operator on "The Andy Griffith Show."