In the back of my mind, I always wondered what might happen if the coin value went up when I was due to get paid.
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Isn't it reasonable to expect that, if a bank account was deemed "safe" by coinbase for selling, the same bank account would be safe for buying
I contacted CB a couple days ago and have not heard back. Very disappointed unless there can be a good explanation from them.
I just signed up with Coinbase and I'll admit I worry about the same thing. The three day delay to pay you either way makes you vulnerable to them choosing to be opportunistic. Unless your behavior on the buy side was very different than on the sell side, e.g. you sold .01 coin a few times and then bought 100 of them, I too would have a hard time seeing how all of a sudden ones dealings are suspicious other than you made a trade that didn't continue to go in Coinbase's favor.
I know that a bitcointalk user named Olaf often responds on behalf of coinbase. You may want to try and contact him directly.