What? There's a toggle to hide episodes you've already listened to. If you have that turned on, it only shows you episodes you haven't listened to yet.
Only on the Latest Episodes page, which doesn’t allow you to group by show. The Downloaded page lets you hide played episodes, but doesn’t hide them for 24 hours (why??). The Shows page … that’s all messed up. You can hide played episodes, but it randomly displays episodes from years past with no possible way to mark them played without first downloading it and then marking it played.
I don't understand. The Shows page lets me hide played episodes and mark individual episodes as played without downloading them. You can click the "..." or long press on any episode in the Shows page to mark it as played.