Calculating Open Prices at a high IV Open. PLUG example.

I had orders get filled all over the place on PLUG trying to calculate using yesterday's closing price and IV. How do you discount the difference between yesterday's IV and the Open?

 

Sold half the Open and half when we hit $54, unfortunately I was not carrying a huge position 40 contracts $45s, $47s and $50s.

 

You were talking about plug option?

 

Yes, the $45s, $47s and $50s plug power. I got the answer from a option god out of Houston. Forget I asked! Depending on order flow, exchanges, price, ect.

 

I estimate option open price by delta. Is that right answer?

 

plus IV.