From Virgin Atlantic 4/22/10:
Travel Disruptions Update
New Bookings on flights prior to May 1st
Due to the exceptional circumstances arising from the closure of UK airspace, Virgin Atlantic took the decision earlier this week to put a hold on any new bookings on travel prior to May 1st, in order to accommodate stranded passengers. As our flying program is now gradually returning to schedule, and a significant number of our passengers have now been repatriated, we will be lifting this embargo as of 12pm today.
Bookings cancelled between 6:00am on April 20th and 12:00pm on April 22 will not be reinstated.
To protect the integrity of our bookings during this period of high demand, we will be enforcing a 24hr Ticketing Time Limit on all new bookings for travel prior to May 1st.
While we will make every effort to accommodate all of your customer needs, availability may be limited on outbound flights to the UK over the next few days, as our top priority is the repatriation of any stranded passengers.