[SunburntRock89]

It's still reasonably trivial to download stuff from iPlayer (using the aptly named get_iplayer). The max you can get is 720p though.

I really like iPlayer as a platform but find it hard to deal with the 720p maximum on pretty much all devices.
You can stream 4K content on about 4 devices and the BBC decides exactly which devices are allowed.

I bought a Fire Stick 4k expecting to be able to view stuff in 4k, turns out they had some sort of an issue with it which they blaimed Amazon for about 3 years ago. You still can't watch in 4k all these years later. The issue they described was super minor too.

Did some resarch with a friend and it appears they have specific certificates installed on every 4k compatible device to protect the streaming endpoints.

get_iplayer now allows you to download VOD content in 1080p.  All but English regional news content, BBC Alba, Parliament and S4C is in full HD, while linear streams are still either 540p SD or 720p HD.

The current Fire TV Stick 4K models and the 2nd and 3rd generation Cubes will let you watch 4K HDR content where they have it on iPlayer.    The 2nd Gen Cube is the only official Amazon device that is supported by the BBC for 1080p, although I understand the current sticks and the 3rd Gen Cube render the VOD content in Full HD.

Do we know why we can't get 1080p streams of the live channels? They all output in it. 

The Fire TV Stick 4K 1st gen (which was sold until at least December 2020) can't view UHD content, although I should've clarified that. www.bbc.co.uk