I haven't contacted av-appletv-feedback [AT] amazon [DOT] com but If I've deduced correctly then app 'id545519333' is the key.
I'm in the United Kingdom ('GB' region on iTunes) but also have a United States (US) account.
The old listing for GB was:
Amazon Prime Video
by Amazon Instant Video Limited [
https://itunes.apple.com/gb/developer/id353141815 ]
Updated: 23 October 2017
Version: 4.8.2
https://itunes.apple.com/gb/app/id454468674
The old listing for Germany (DE) had the same developer ID but a different app ID:
Amazon Prime Video
by Amazon Instant Video Limited [
https://itunes.apple.com/de/developer/id353141815 ]
https://itunes.apple.com/de/app/id457830447
The old listing for Austria (AT) was the same as DE:
Amazon Prime Video
by Amazon Instant Video Limited [
https://itunes.apple.com/at/developer/id353141815 ]
https://itunes.apple.com/at/app/id457830447
The new listing for GB is:
Amazon Prime Video
by AMZN Mobile LLC [
https://itunes.apple.com/gb/developer/id297606954 ]
Released: 06 December 2017
Version: 5.0
https://itunes.apple.com/gb/app/id545519333
This is the same listing in the US:
Amazon Prime Video
by AMZN Mobile LLC [
https://itunes.apple.com/us/developer/id297606954 ]
Released: 06 December 2017
Version: 5.0
https://itunes.apple.com/us/app/id545519333
I, as a GB user, have safely uninstalled 'id454468674' and presume that DE and AT users can similarly safely uninstall 'id457830447', as 'id545519333' appears to be a consolidated app for all 155 'App Store Territories' [
https://developer.apple.com/library...nnect_Guide/Chapters/AppStoreTerritories.html ].
Therefore, if you remove the geographic region from the URLs then you should be redirected to your local iTunes Store, i.e.:
Amazon Prime Video
by AMZN Mobile LLC [
https://itunes.apple.com/developer/id297606954 ]
Released: 06 December 2017
Version: 5.0
https://itunes.apple.com/app/id545519333
These 155 territories include the US, United Kingdom (GB), Germany (DE), Austria (AT) and Japan (JP) - the five countries where "customers... can watch videos purchased or rented on Amazon", Belgium (BE), Canada (CA), France (FR), India (IN), Italy (IT) and Spain (ES) where "customers with Prime can stream a vast library of movies and TV shows at no additional cost" and 144 other territories which charge $2.99 USD or €2.99 EUR per month.
Of the 200+ territories in which Amazon Prime Video has been available since late 2016 (
https://www.businesswire.com/news/home/20161214005486/en ), this therefore leaves a further 45+ other territories whose residents will still have to pay $2.99 USD or €2.99 EUR per month but will also either have to download the iOS and/or tvOS app from the App Store in the country closest to them, or access the service through
https://www.PrimeVideo.com (
https://www.businesswire.com/news/home/20171206005741/en ).