Originally Posted by
fassy
Hmmm, no - there is a lot of interpretation which can be done here on "subject to availability of seats". For me (and some friends which are lawyers) means exactly that, a free seat in the booked cabin class. Not in the same booking class. Otherwise they would not rebook you either if e.g. booking class K is not more available and they can only offer e.g. Y.
Good luck with that! Most carriers will allow you to rebook to a later date only if the same booking class is available. Maybe SK exceptionally allowed you to rebook to a later date in higher booking class, but I doubt this is the general policy of SK. In my view you are not entitled to ask for rebooking in any (economy) booking class (say in expensive Y class) if the original booking class is not longer available. Surely, it such not be entertained to book a super cheap K class fare in low season (say for Sept) and following a schedule change ask to be rebooked to a flight on say 22 or 23 December (where K class is sold out long time ago).
As already stated this does not apply to rebooking "at earliest opportunity" where you are indeed able to ask to be put on a flight regardless that your booking class (or even service class!) is no longer available