SR

It sounds truly horrendous and another example of a situation for which there is absolutly no excuse. Personally I'd go for option 1 - is it Business class for the entire routing or could they provide Y for part of the flight. Alternatively try to get some kind of resolution on compensation in advance so that you are not left dissapointed. I think half your miles back is reasonable depending on what kind of change you need to make on your return.

FM

and once its all sorted, straight down to little creatures in Freo for a few well earned beers....

glad to hear you got sorted and you will not be stuck in WA, watch out for cyclone billy up north!!