It's possible that Entercom has looked at the fall ratings, realized that both WCMF and WPXY (the other station where personnel bloodletting has occurred) are not going to be able to grow their respective audiences any time soon, and decided to dump them both in their diverstiture package as an alternative to selling off the clearly surging Warm 101.3. They have to sell off enough revenue and ratings points to make the FCC happy, that much is certain. A four station cluster of WCMF, WPXY, WFKL and WZNE gets that job done, and is a bigger reduction in overall cluster operating costs to the company. It's also an easier package to sell than the three station cluster they've had on the block all fall and winter which includes only one full B (WRMM) plus two class As (WFKL and WZNE), and so far has attracted no takers at an acceptable price.
If they're going to dump CMF, PXY and the two class As as a group, they need to reposition WBZA to cover more of the territory that they lose if they let go of rocker WCMF and CHR/hot AC WPXY. You can do that by spreading out the Buzz's music mix, while keeping what amounts to personality Hot AC presentation with a generous slice of rock thrown in.
If I'm right, and they are putting those four stations on the market as a package, what they're doing with the subtle repositioning of the Buzz is a natural outgrowth of that.
That of course begs the questions of who would buy that four station cluster, and what they'd do with it, but that's for another time. Entercom probably isn't worried so much about that at this point--just about getting the best price for the stations they have to sell, and maintaining a profitable cluster of their own which is strong in the demos where they choose to compete, no matter who they end up competing with.