More senior airmen, fewer overall enlisted expected in next few years

Yup.

I was a SRA at that time (in '74-78) and the AF was taking volunteers for early out. I stayed in, but it was virtually impossible to make E5 in four years due to the glut of Senior airmen and E4 sergeants as well as a glut of 16 year plus E5s. Things got rough for those guys to make E6 quickly or they were out with no retirement!