It's by no means certain that WFNX-101.7 will flip to a talk-based format.
However, I could see CBS radio eventually "blowing up" one of their remaining FM music stations for a simulcast of WBZ-1030 (I expect that the WBZ-FM call letters, now on 98.5, would be moved to the station simulcasting WBZ-AM with 98.5 perhaps changing calls to something that spells out "Sports Hub"). But it might not be for a while.