Yes, it's still a 14 day ban for a first offence, regardless of your membership status. I've been banned on f2p characters recently, and they received 14 day bans.
After a 14 day ban is over and you're caught again, a 21 day ban is issued, followed by a 28 day ban, and finally a permanent ban.
In regard to your other question, I believe they watch the account for a certain period after the ban has lifted. I base this on personal experience:
Note that that was on an F2P account; I began botting immediately after the ban was lifted, and within 12 hours I was already banned again. In contrast, when my main was banned for macroing minor, I stopped for one month before I resumed botting, and have yet to be banned over a month later.