Found this regarding an EASA equivalent to the FAR 10% rule.
ICAO Annex 6-4.3.6.3
To have an additional amount of fuel sufficient to
provide for the increased consumption on the
occurrence of any of the potential contingencies
specified by the operator to the satisfaction of the state
of the operator.
(Typically a percentage of the trip fuel - 3% to 6%).
Will talk to dispatch on Monday regarding the 10% Flag fuel FAR any relief that may be given. If in fact there is relief, I suspect it would appear in the operators OpSpecs.