It's not April?
Sounds good although without sounding rude, if he was really serious it takes more than just an email. You have to have emails, make tours around the airports, meet marketing teams, ground handling etc etc... even if it's just a plan.
Also while a new airline sounds fantastic especially to be based at Doncaster, at the minute it will be VERY VERY hard to get customer support. People like to book with the well known airlines, the ones that they know or feel have a good financial background, well heard of etc etc ; Are people really going to be willing to risk their money on something new like this in the current market...? It's still very tough out there!