No idea.
Taken from IoM airport website:
"In response to the COVID19 Pandemic and in line with Emergency Powers, ALL persons arriving onto the Isle of Man MUST be in possession of a Letter of Exemption issued by the Government Chief Secretary.
Any person arriving on the Isle of Man without a Letter of Exemption, will be refused entry and will be required to return to their point of origin at their own expense.
We currently have a limited schedule of services, which is in place to support patient and key worker transfers. Outbound flights are available for booking by any person wishing to leave the island, however, return travel is currently restricted to those persons who are in possession of a Letter of Exemption issued by the Isle of Man Government’s Chief Secretary. Letters are issued via official channels, and if you are eligible, this will be processed on your behalf by the appropriate sponsor. Please DO NOT contact either the Airport, or the Chief Secretary’s Office for information regarding Letters of Exemption.
Flights are currently operating as follows:
Isle of Man to London Heathrow 6 x weekly operated by British Airways (bookable via www.ba.com)
Isle of Man to Liverpool 12 x weekly operated by Loganair (bookable via www.loganair.co.uk)
Isle of Man to Manchester 6 x weekly operated by Loganair (bookable via www.loganair.co.uk)"
Looks like you can leave if you can find a flight.