I was told over the phone (so believe what you will) that using Auto Upgrade will not allow for the combined miles rate as Auto Upgrade does not 'release' the other legs of travel but rather processes the miles upgrade for that specific leg separately. I've lost 30k miles to Auto Upgrade needlessly. If you're diligent enough, just keep checking EF/MMB as Auto is for lazy people AND it is not instant as soon as there is availability. There is definitely a delay.

I have had Auto Upgrade in place for Z, I called and they processed the upgrade after seeing availability on EF, even though Auto Upgrade hadn't done its thing. I hate to be a tin foil hat wearer, but I reckon there might be priority given to I/O Plat with Auto Upgrade on over say, a silver or low gold.