Much as I have sympathy for some of those on the front line of the borders agency, which does seem to have been cut back too much cope with the influx of visitors to the UK, I always felt it was a somewhat cynical exercise by the PCS (?) union.
I am not entirely sure what concessions they feel they have won from the government - as best I can tell, the govt have not conceded anything - It seems more a case of recognising the potential harm of the poor public relations such a strike would engender.