Seems to be a series of charters for (school kids?) has been 4 visits in this series similar to last time (possibly last year?).
Also a quick note that KLM have slots in for 4x daily to MME over the winter, all Fokker 70's. The new flight runs around lunchtime and should prove popular with connections off the later Atlantic flights if it goes ahead (remember they had 4x in the schedule last winter and for this summer until they pulled it, third time lucky maybe).