well you would have to sell lower (430) and hopefully buy lower.  Do the math and decide if it all makes sense.
Selling now at 430.  If sold at 430, then you take 120 loss per btc.  If you think it will go to 310 (which would be a break even point....if my math is correct) then consider doing so (remembering it was 339 ish a few weeks ago....might or might not break that)