This is the 3rd time this has happened to me in as many months with 3 different stocks and i can never get an answer as to why. Placed order with IB to sell a GWK2 Jan 90 call for $2.45 at 10:40 with the spread at $2.35x $2.60, option modeler showing $2.46. 10:44 spread is still 2.35x2.60 only now the model price is below my ask. 10:45 my ask is now displayed. I thought with electronic transfer the exchanges had to post immediately instead of holding the order to see which way the market was moving. This was on Philly but have had the same problem with CBOE.