Do I need to explain that an MoC process includes manpower, aircraft, parts, approvals, training, facilities, and every other factor involved in being ready, all with timeline? Surely not...
From what I can assess, the aircraft are already in Europe, so are now a minor factor, with some evidence that crewing is the limiting factor. Even if they are a factor, that'd still have been known from the timeline.
The main challenge was always going to be recruitment. For pilots, the timeline should have covered advertisement of vacancies, selection and interview processes, issue and signing of employment contracts, time for currently-employed pilots to serve notice, company induction, Operator Conversion (which I'm sure you know is not the same as an OPC, and required for all joiners), and availability of Line trainers. This isn't new, and is not rocket science. I'm sure CHC would have had a plan for a 'transition crew' of current company pilots to do the work until the new starters would be on line.