@Anonymous User
Welcome to the forum.
Season5 is the current season and so episodes are on catch-up. This means that they are only available for a certain number of days after first airing live, and the countdown you see is showing you how many days before the episode expires. Episodes 1-8 have already expired.
If you missed them you'd need to wait for them to be added as a boxset sometime in the future.
Do you know whaen season 5 will all be available as a boxset?