From below neither Aer Lingus or Stobart have a UK AOC and from 31st October will require a foreign carrier permit which will not be given for
domestic services. Note from the AOC holders, both Ryanair and Wizz already have UK AOCs
https://www.caa.co.uk/Data-and-analy...-certificates/
https://www.caa.co.uk/Commercial-ind...arter-flights/