I had trouble checking in last night for a LAS - SAN - LAS flight using the IOS app. The first sector was fine. When trying to check in for the return from SAN - LAS all I get is a "Something went wrong. Please try again or check in at the airport" error. I was able to check in using www.alaskaair.com but even that was a struggle with the website stubbornly refusing to show anything other than the outbound sector.