EESDL
EESDL - the reason for your DLM delay was most likely because that aircraft (G-OJMR) was delayed first thing in the morning on the ZB564 to TFS. The aircraft had an ongoing tech issue which I certainly hope you feel would be better to get sorted then for you to go on an aircraft that potentially has a big issue which could result in the aircraft returning, or flying at a risk. Delays always happen and considering how tight the ZB schedule is on certain days, you have to respect the fact that a little problem in the morning does have a knock-on in the afternoon slot.
I have thankfully never seen Monarch cancel a flight, a delay might be annoying but would you rather get to your holiday destination in safe hands rather than not at all?