This is currently happening with Canadian airline WestJet. For many years they only flew a single aircraft which made maintenance much easier (staff trained on

This is currently happening with Canadian airline WestJet. For many years they only flew a single aircraft which made maintenance much easier (staff trained on a single aircraft, parts are easier to keep in stock). They since purchased a few larger aircraft to fly to London and Dublin and have been plagued with maintenance issues. Passengers are getting stuck in London while WestJet scrambles to fly in a mechanic and parts to fix the planes.