The topic is said to have come up on Continental before - but it is not found in either FAQ or FAQ development thread:
What does "Confirmed reservations" actually mean for elite members? And for non-status holders of economy tickets?
The Continental website:
http://www.continental.com/web/en-US.../services.aspx
states
Confirmed Reservations: Platinum Elite members receive confirmed reservations -- even when a flight is sold out -- when purchasing an unrestricted Y class ticket at least 24 hours prior to departure. Gold and Silver Elite members must purchase at least 48 hours prior to departure. (Available on most flights operated by Continental Airlines and Copa Airlines only. See SkyTeam Elite Plus benefits for long-haul SkyTeam-operated flights.)
What does then happen if a flight is sold out and in due time (48+ hours ahead) silver or higher elite members wish to buy full-fare economy tickets? Assuming that any expected cancellations and no-shows are already covered by overbooking and the only way to accommodate additional passengers is to involuntarily deny boarding to some holders of confirmed tickets?