I believe and I hope to corrected if wrong, that as long as you put enough in to cover the main ring gear, you will be fine.
I think the bronze bearing in the pilgrim will pass oil into the gearbox, so it should be re-replenishing while running.
I hope so otherwise I will be in deep Doo-Doo!
The reduction box on my Scott gets oil via the bronze bush in the Pilgrim pump. I always turn on the oil for a minimum of about 20 minutes before going out. If I take out the oil plug and turn on the oil, it will after a while come out of the oil plug hole, so no worries. I did this one day to make sure the gears were being lubricated.