It’s pretty simple stuff and not worth getting knickers in a twist over.
Ask yourself two questions;
1/ Am I committed to this airfield?
and
2/ Will further delay result in me landing with less than FFR?
If you answer yes to both questions then declare ‘Minimum Fuel’.
If at any stage it becomes apparent that you will land with less than FFR declare ‘Mayday Fuel’.
Thats it.