Miles earned on or after July 1, 2008 will expire after five years.
Previously, miles never expired.
The announcement claims that miles in the majority of international programs expire after 18 months or three years. What they don’t say is that any activity in an account with most of those programs will extend the validity of those miles another 18 months or three years.
That doesn’t seem to be the case with this new change to Skypass. Instead, they’ve gone the route of programs like Cathay Pacific AsiaMiles — use ’em or lose ’em.