For me, starting film sound post with a locked picture cut is practically unheard of these days, even on lower budget films. And big budget and/or VFX films tend to make picture changes right through the predubs and the final mix. So what do you use to conform your ProTools session to new picture cuts?
I'll add my answer below but am interested in any other apps and/or strategies to deal with complex sessions...
I use Conformalizer http://www.maggot.co.nz/software/conformalizer.shtml
My approach is to always work in a single PT session with all six reels (eg R1 @01.00.00.00 R2 @02.00.00.00 etc) so I select all tracks including video, markers & audio & then cut/paste all six reels so R1 starts @07.00.00.00
That way I can tell Confommalizer to source the material starting from 07.00.00.00 and it recuts it back into sync via the changelist EDL to 01.00.00.00
Apart from conforming the audio into the new sync, it is also VERY valuable to cut the QT track, as then you can switch between the new QT and the old conformed QT tracks & visually verify any sync issues or VFX updates....
It also means if any material got lost between the cuts, I can skip down to 7+ hours & review how it used to be and access the original material...
I know some people use Virtual Katy or EdiTrace - any experiences? Not sure what else is available/works well? FWIW Conformalizer works incredibly well!