yes most earnings come out after hrs, but when the market opens the next day on a gap, you'll be taken in at market price, sinse price gapped above or below your order
once your in the trade, you can cancle the other order, or use an OCO order if your broker has them.
I dont know much about options, but i do know, that id go long athn rather than short, AND the march 30 calls have the most volume...investors are betting that in the next 3 weeks, athn will be up to 30
PSA looks like a good trade for next week.