a word problem

miriam had $M in her checking account. She deposited a check for $N. The citibank machine said she had "N+M available now."
Let's say miriam writes two checks (C1 and C2) and makes one transfer to another account (T). Let's say fruther that C1+C2+T < M+N. Will miriam's checks bounce? If they do bounce, what does "available now" mean?

arggg...
(and apologies again to the person to whom this actually effected...)


the moral of the story is, of course, not to trust machines when they tell you things that you think don't make sense/may not actually be true...