The offer of Pri25 for both pilot groups on both airlines came from CX without being asked for. It was confidently announced in Jan 2014 with a start date of Jan 2015 and at first, it seemed a good thing. It was about the same time as KA took over PEN and My guess it was a CX manager's knee jerk reaction when it looked like KA was going to take over more of the local destinations where many CX pilots like to live and who would now be lower on the priority to make commuting a viable lifestyle option.
However, when the details were made known, it was realised that there were a few devils in the details and it wasn't such a good deal after all. Since then, it's all gone quiet and CX seem not to want to discuss it as they realise it will open a large can of worms. Having had it offered and then taken away has annoyed some KA pilots. In the meantime, one benefit for CX management is that the CX and KA guys are even more divided and consequently easier to conquer.