In the grand scheme of things, the number of cancellations are a mere drop in the ocean. When taking a step back and looking at the whole operation, one needs to bear in mind the size of the flying program. CFMU reveals that there are 1086 flight plans filed today with an EZY callsign. Even if 10 flights were cancelled then that just represents 1% of the whole network.
As an aside, there was a Air Italy B763 operating for easyJet out of LGW yesterday. Are we going to see more ACMI aircraft being drafted in over the summer???