It’s best to explain with an example: Our AUDUSD Administration Fee is $7.5 and it’s ‘grace period’ is 10 days.
If you open a AUDUSD position on a Monday then there will be no Administration Fee on Monday night (grace days will reduce from 10 to 9 after Monday End Of Day [EOD]).
On Tuesday night there will be no Administration Fee (grace days will be 8 after Tuesday EOD).
On Wednesday night there will be no Administration Fee (grace days will be 5 after Wednesday EOD… 3 days as Wednesday counts as 3).
On Thursday night there will be no Administration Fee (grace days will be 4 after Thursday EOD).
On Friday night there will be no Administration Fee (grace days will be 3 after Friday EOD).
On Monday night there will be no Administration Fee (grace days will be 2 after Monday EOD).
On Tuesday night there will be no Administration Fee (grace days will be 1 after Tuesday EOD).
On Wednesday night there will be 2x Administration Fee. Wednesday counts as 3 days Administration Fee and you had 1 days’ grace left. Therefore, the Administration Fee is reduced from 3 days to 2 days. You will be charged 2x $7.5 = $15 Admin Fee.