Hier ein Auszug aus den entsprechenden FIA-TRegeln:
During a season each team will be permitted to use four drivers (excluding any third drivertaking part in either of the free practice sessions on the first day of practice). Changes may be made at any time before the start of the qualifying practice session provided any
change proposed after 16.00 on the day of scrutineering receives the consent of the stewards.
Additional changes for reasons of force majeure will be considered separately.
Nachzulesen unter:
http://www.fia.com/resources/documents/ ... _Reg_a.pdf
Wichtig erscheint mir dabei:
Additional changes for reasons of force majeure will be considered separately.
Das lässt wohl einen weiteren Wechsel, falls sich noch ein paar Williams-BMW Piloten verletzen, durchaus möglich erscheinen.