I haven't ever had 4 sick calls in a year, but I was told by a union rep that the union grieved the 4 in 12 policy, and lost when an arbitrator ruled (for whatever reason) that it is reasonable to expect pilots to be healthier than other people. The reason the grievance went to an arbitrator is because the company fought to maintain their policy. For the record I haven't read the ruling but was told this directly.