@PKauto
I am still seeing Line of Duty on Britbox (Seasons 1-6) available and is playing fine. These are playing without ads. You should be seeing the same thing if you have a subscription to "Britbox on the Roku Channel".
When dealing with subscriptions, you can subscribe directly to the provider (ie. Britbox) and pay them directly, or you can subscribe "through" Roku (ie. Britbox on the Roku Channel), and pay Roku which then pays Britbox. Some find consolidating all their subscriptions under Roku makes billing more convenient, while others find it more suitable to deal with the provider directly.
It also looks like many of the free AVOD (ad supported video on demand) channels/apps are also showing seasons 1 - 4 of Line of Duty. These include the Roku Channel, Plex, Pluto, Freevee, Tubi and others. These ads help cover the licensing costs of streaming the content since there is no subscription cost to the free channels/apps.
You will find with streaming that you can often find the same content available on both subscription (paid, normally ad-free) and free (ad-supported) services at the same time.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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