I was thinking one trip this weekend and one two weeks from then. And maybe a couple of small scouting outings.

as well as time I find that mid afternoon is a really good time to explore for lots fo reasons.
1) its alot less suspiscious to see a large group walking around in the day than at night.
2) when exploring a building at night its easier to see our lights from the outside
3) plenty of time and daylight for photos.
4) enough time to meet up, get in, explore, ect. by the time we make it to the roof it'll be sunset and I'll tell you it's quite the sight.

how I see this one is meeting up for lunch in the area(around union station) driving/ bussing out, getting in, exploring floor by floor, ending on the roof, then exiting.
one concideration is that the building is used for filming so sometimes there are film crews.

anyhow thats how I see this working out and how it worked in the past. but I can always do things differently if need be.