Mark, your problem is pretty simple.  If you dont want to clean up now, some timely candle dinners and some flowers might be able to buy you some time !!!! ;D

In a previous post I wrote the 757 had extra fuel over what I have seen in other planes. My mistake. regulations in USA stipulate, enough fuel to make the flight with extra :  30 minutes, then enough for the aleternate and then an extra 45 min.  This for all IFR planes.
The other flight plans I checked was AC, different rules for IFR.
Enough fuel, regardless of weather to complete the flight. then anough fuel for alternate, one engine out, low altitude, and then an extra 30 minutes. Must have improved weather from destination in the first place.
Simple enough, two countries, different rules.

Happy flying !

PS  I also gained three flight plans.  One extra !   :o

Raymond   Boeing or nothing
KFLL  South Florida