saad's post is the most important item to note on this thread.

ALWAYS look at the actual T&C's first, then ask any questions of the FT board as you can best believe many here have sliced/diced the T&C's to make sure to get maximum benefit from the loyalty given to their particular chain of choice.

That said, I had consecutive nights booked when I first joined HHonors (my first hotel program) way back when, thinking "how hard can 25 stays be to get top tier!!??!!"
I got lucky, read someone's post on FT and was able to switch up the properties w/o penalty.