FAZ - I would sell as soon as you are in the money. In general, I avoid holding 3X levered ETFs overnight unless I am confident the market will stay in a trend. Too much risk and volatility with these.
Also, the bank stocks have A LOT of room to run. Sure, there maybe some profit taking, but they have all been beaten down so much, there is a lot of upside room in the charts.
Lastly, don't fight the tape. Sure we saw a lot of short covering today, but this rally is ON! The volume today was big. The big boys who benchmark themselves against the S&P do not want to be down YTD when the S&P is up. And a lot of funds are down this year. Been a very tough year to invest or trade.
I am down YTD after being up big thru July. Still time to make it up though.
Hope this helps!