This Earning's Season has proved nothing is every guaranteed. IBM is definitely one example although it appears to be crawling its way back up. The closer you are to a Stock's Earnings Date the bigger the difference in the bid/ask price. I bought the $36 Call using the 8/21/2020 expiration for $2.20 the bid/ask price was 2.20/2.21. You have to be patience and look for the price to turn "red" and then either bid lower and/or wait for the price to go down. I placed the trade this morning.