7.1 channel order

I am a little confused about 7.1 channel order.
When I use getChannelIndexForType i get the order “L R C Lfe Lss Rss Lrs Rrs”
I think the standrad order for 7.1 should be “L R C Lfe Lrs Rrs Lss Rss”

It seem to work as expected anyway in the plugins…

But how to pick out the channels and get the correct order manually?