UPDATE: Relax, Radioman123, because Jay Perez, a.k.a. "Your Brown Beauty On Duty," is back doing afternoons. So the 50s and 60s oldies are not totally gone from the station. This is part of a trend of other True Oldies affiliates adding local talent, like WLS-FM 94.7 in Chicago, for example.
BTW, I forgot to mention in the original post that the format tweak (not really a flip, since it's not a totally different format) came following the retirement of Lee Marshall.
But, I think that the True Oldies Channel should be renamed the True Classic Hits Channel, since the 50s are pretty much gone from there and there is a lot of emphasis on the 70s and even a few early 80s songs here and there. I'm sorry, but in my book, 70s and 80s music does not qualify as "True Oldies;" more like the above-mentioned hypothetical re-branding.