oh i dont know what is going to happen with the stock, i just know that bp vol was lower during the day. i bought the june 30 call at 2.16, 2.04 and 1.98 at different times during the day all with the stock down between .77 to .83. So explanation must be vol.
I traded the 30 calls three different times during the day, during a four hour period, vol changed to the equivalent of 12 cents or more during that time frame. Vol and time decay will nail these suckers every day. Vol kept changing. Perfectly normal on a market down day, especially when you are dealing with a crazy bp stock.
if you want to understand option pricing, take at look at "option pricing and volatility" by sheldon natenburg