Bergerie1,
It’s a bit like the story of two Flights A and B with no weather problems at their destinations.
A plans to go to airfield Z with airfield Y as the Alternate. B plans to go to Y with Z as the Alternate. Flying time between Y and Z is say 30 mins.
Both A and B arrive at their intended destinations at the same time and due to some airfield delays have to hold for say 20 mins.
Both are now down to their Reserve + Diversion Fuel. ATC advise of a further 5 mins delay, then both airfields will be open.
Do they continue to hold at their respective destinations or divert?
If they divert, then A and B will pass each other halfway between Z and Y and both will arrive at their respective Alternates with only Reserve fuel remaining.
If they both continue to hold at their respective destinations for a further 10 mins say, then both will land with Reserves + most of their Diversion Fuel remaining.
Which option is safer? (Both are legal).