One of your bigger problems may be budgeting. If they’re not finishing the building for two years, how many “interim versions” are you going to do before that – or are you not going to look at it until the building is finished?
I’d guess you might want a couple of early “tests” to validate process / show up any probs to you and client.
I’d also guess it will save you a whole lot of time if you resize in PPro – otherwise you really probably want a batch processing script in Photoshop or your resizing will take forever.
You could simply drop shorter lengths of stills ( a week at a time?) into timelines, set your speed acceleration and render a rescale then .. if you’se skipping lots of frames then that’s lots of resizing you don’t have to do/
And of course in two years time, you’ll maybe be delivering this on BluRay or HD DVD in high definition ….
AND you’ll be using PPro 3 on a 64 bit Vista system with bags of RAM, so a heavy stills sequence might not slow you down too much!
I’ve timelapsed successfully here with PPro. I found it necessary to edit the source footage a fair bit to keep things interesting.