I book in advance - usually 4-6 weeks. Dates aren't flexible, and LPL is no good - has to be MAN or BHX. Not unusual for someone doing business on the IOM and can't afford to lose a day a week because of inconvenient flights.
But a quick random check; return fare IOM to LPL leaving Monday 1st Feb a.m. returning Fri 4th Feb evening is £175 including card fees (excluding seat reservation, insurance and luggage).
Cheapest crossing that week Mon-Fri (if the times are any use) is £118.
Book four weeks in advance from Manchester to IOM (more typical for me) and it's £143 or £111 (on the same basis).
Bearing in mind that the more expensive figure is actually the only practical flight for me (and a lot of others, judging from the price structure), these fares are a lot higher than 12 months ago.
Yes, I could book a Liverpool flight for April at a very reasonable cost. But that's too far ahead, and I don't think it's any coincidence that Easyjet are bringing in their new LPL-IOM timetable then (which offers real competition to Flybe, at last!).