"Amazon Sales Channel" vs "All-New Amazon Sales Channel"?

Like others - we tried the Shopify “Amazon Channel” app a couple of years ago - and there is little good that I or most other users can recommend about it. (See the apps store reviews - 120 x 1 star reviews out of 175 in total).

But I am now seeing something called the “All-New Amazon Sales Channel” in Shopify documentation - although is doesn’t appear to be available to our store (in Canada) though Sales Channels.

Can anyone tell me about it? Does it work? Is it an improvement? When might it be available to our Canadian Based (USD) store?

Can someone from Shopify please read this and reply?

I have tried speaking with Shopify Chat Support and they know nothing more than the 2 pages of documentation that I posted above.