Hi Ben, posting at the same time i see!
You dont normally get First Class tier points or miles though if you do the $50 one-way First Class upgrade during online check-in or at the airport.
True. HP/VS state that this airport upgrade is at a reduced rate so not elligible for miles/tier points. So to take advantage of earning tier points on the short internal flights you would really need to book your F fare in advance - which can be costly.
As its only 1TP, i would be tempted to upgrade at the airport and have the comfort without the huge cost.