Think that with the auction of FBI price will drop to 530-540 and then can be move up !
So, HODL and wait to 540-550 for buy

If that is the case, it'd be stupid not to sell. You should sell now, and buy back when it hits the 550.
That's right. Basically, the concept here is to be patient to maximize the profit you can get. It's not easy to do that, especially when the market, and many of its assets are down and are continuously going down, but then, that's just how this market works. You can't succeed here if you won't be patient and wait for the perfect time to either buy or sell your holdings. So, if you must wait for you to get the max profit of the coin your eyeing, then that's just the best move to do.