IATA requires all airlines participating in interlining to charge the same fee. To charge alliance partners less is a violation of trade/commerce in most countries. However, AC does charge AF and BA and CX and any other carrier that has a commercial agreement with it to provide feeder traffic on domestic legs, a certain minimum fare class (which I believe is H, or used to be H for economy, and pretty much full J in the front) for those segments. These carriers would like to be able to pay a lower tarriff, but it is AC's call what it will charge an international competitor. (Since there is a standard tarriff for the through fare, these carriers must deduct what they pay AC from what they collect from customers, and thus end up losing a fair amount on the gateway international segment.)

Obviously those carriers using AC would like a better price deal, but have noplace else to go until WS gets its act together. It's now been four years since it first talked about providing limited interlining to carriers like CX, BA and AF, but it can't even get this act together. Once it can interline luggage, it can enter into commercial agreements that deal with selling domestic legs, and thus offer a lower tarriff than AC does.

Another delaying factor has been the fact that WS only offers economy seating, so the more lucrative Business and First class customers that these international carriers would like to court, would not have that seating on the domestic Canadian portions of the trip...a fair disincentive to fly them.

As for bilingual FAs, WS is starting up service to YQB and claims to have close to 400 bilingual FAs, and getting more.