@scifi,
Quite often conditions change on the way out. QNH changes from ATC, wind sock, previous aircraft getting their TO clearance with the wind. I am not talking about the cases where you have no reason to think that things have changed. How many times have you taxied out and runway in use changed? Because conditions change. If you got a runway change, would you just change the runway on the EFB and recalculate without taking into account that the wind changed 180 deg? Itīs exactly what I am talking about here, just without the rwy change.
thanks everyone for comments, seems like there is no decisive legal stuff, and that it is up to the operator to pose limits on this.