Well, in this case arguably the solution is not to exercise if you can't pay the tax bill, absent selling your stock. Exercise early, pay little tax because th

Well, in this case arguably the solution is not to exercise if you can't pay the tax bill, absent selling your stock. Exercise early, pay little tax because the FMV is low. Exercise late, pay lots of tax because the FMV is high. Exercise late and sell, pay lots of short-term cap gains tax. Exercising late, while still unable to immediately sell some shares to cover the tax bill you know will come seems like taking a huge risk.