Thanks everyone for your input. I am not very hopeful that AC will give in at all. I have 1 Asia trip booked and 1 TATL before December 31. The Asia trip is in Tango (so no 50% extra Status miles anyway) because I could not justify to myself to pay almost $1000 more for Tango plus. According to my calculations I will just barely squeeze to 35K this year, last year I easily got to 60K. Lets hope there won't be any more IROP or I won't even make the 35k.

So if this kind of situation arises again what is the best way to ensure getting the full miles? Keep insisting to be rebooked only on AC operated flights? Ask the agent to please put me on a fare class that will entitle me to the full miles?
With winter approaching and getting close to the qualifying year end if I miss out on Status miles on 1 more flight I will not reach 35K.