Lisa loves bald men Jack, I actually would have a full head of hair, but I shave it off to keep her happy.
If you were serious Jack, unfortunately I can foresee just a few problems.
Would Butterfly Conservation be willing to put their name such a product.
We already produce UKB/BC calendar, which would mean we would run in direct competition with ourselves.
Then there's the printing. To get a decent discount ( to be a good money spinner ), you need to order in May. As BC wont take the financial risk of producing a calendar, and UKB is run by volunteers, and has no money.

Then someone has to take the financial risk that, all the printed copy's will sell. And be willing to tie up their own money until December.
Regards Guditch