How much head room can you get for your plants, strain, and care will determine how long it will take.
And with a 1 foot flouro tube, it's going to go alright for a little while, but after your plants get to a certain height (usually small) it's growth will most likely freeze (I tried many cheap flouro grows when I was first learning) until you get more light. I hate to beat a dead horse but a good HID system really is the way to go, I had to bullshit my taxes (the IRS was pissed) to get the money together for one, but it worked sooooo much better!
Anyways, expect roughly 2 months after you switch to flower for the buds to be ready, then (this is going to piss you off) You gotta cure em', if your impatient this will take a month. If you want them to reach thier full potential, 3-6 months. Sorry, but it's just the way it is, takes forever to get the first crop, but if you keep a veg area and a flower area, you can keep a new crop rollin' in at the end of every flower cycle, and eventually, you got something ready every couple months.
What a pain in the ass it is to get good pot! But it's sooo worth it.
peace