We don't know what lies behind easyjet's decision, but it may be that Stobart are to be congratulated, and they've at least partly achieved their objective. The only problem is they've gone and got themselves two rather nice E195 aircraft which need to be kept busy and as full as possible. Obviously competition on your better routes can't help.
Perhaps this is all very civilised. Maybe easyjet are happy for Stobart to fill in gaps in their schedule, such as a mid / late morning flight to AMS.