FLPLN amendments by Pilots while airborne
In airline commercial environment is it possible for pilots to amend elements of their flight plan while airborne (by informing ATC ) ?
To be more precise :
Can you ask for a specific airway segment(s) not part of your original flight plan ?
Can you nominate while you are airborne your destination airport as a non-alternate destination (If it satisfies the criteria)?
Or all of the above have to be done by the company filing that on your behalf while you are airborne (assuming you can reach them to ask for it)