Personally, I don't believe a decline in BA pilot's T&C's will have a significant effect on the majority of pilot T&C's in the UK whatsoever...certainly not in the short to medium term. It might if you're VS, AF, KLM or LH...
I second M.Mouse's analysis, and go as far as to speculate that BA Pilots T&C's have negligible effect on non-UK Airlines. There are so many direct and indirect barriers to pilot employment mobility in Europe, (particularly across national borders) that the lure of better T&C's somewhere else is not often enough to cause a stampede for the exit. The correlation is more direct with the likes of VS and BMI, who, as I understand, benchmark their T&C's to BA anyway.
Those of us who are employed by the likes of KLM, AF, LH etc, nevertheless continue to watch the developments at BA with keen interest, and with best wishes to the BACC........If BA successfully set up OS with a third party pilot workforce, it may be only a matter of time before AF/KLM or LH decide to do the same!!!