It doesn't surprise me that this interest in leasing QR aircraft to mitigate the disruption of the strike is generating very strong feelings in the MF crew.
There is a wider irony - the strike is about not restoring travel benefits to crew who have exercised their right to strike (I am surprised this is legal btw), however, this very act of holding firm on this may discourage crew members who haven't been on strike yet from taking part in July.
Whichever way you look at it, this isn't looking good for MF. BA are clearly determined to break the strike (and the will to strike).