I seem to remember him saying he would pull aircraft out of the UK and move them to Europe if we voted to leave.
If you live in France / Benelux / Germany etc and fear risk of exposure to C-19 whilst flying aboard an airliner, you have an easy alternative. Drive to a Southern European resort in your own car maintaining your own family bubble and avoiding any possibility of ending up in a tiresome paperchase for future travel vouchers or refunds. But the UK market is a quite different proposition: this is an island nation. For most, you either fly to the Med resorts or don't bother travelling. Taking a car via Eurotunnel or a ferry is an option, but an expensive and physically demanding one. Simply put, the market for short-haul flying is much more resilient in the UK. MO'L is well aware of the allure of a captive market. Never underestimate the effect of a relatively expensive sea-crossing on alternative consumer choices.