Thanks again really is a big help
Ive read that correct charsets are important, i take it that plugin handles that correctly ?
Do you know if plugin should work fine in WP Multisite environment with network childs domain mapped with their cctlds ?
Re: "using x-default and removing the canonical is nonsense" The dev just meant if going down route of NOT using canonicals AND using x-default in the hreflang then would need to suppress Yoast in those instances.
Re: "In my example, I used two very similar (if not the same langs), however there are things that change, but those are minimal (take as an example a car "hood", in England a "bonnet"). As those are such minimal changes, I don't think a specific version for GB is needed if you are already serving a US version (that's up to you)." Would you say the same if phrases containing these regional variations (hood vs bonnet) were on your target kw list ? Since i find that whilst Google is getting better at semantic relationships between words i think that they do need to be specifically targeted/appear in content & meta data in order to rank for them, or at least increase chances of ranking for them.
Also re your final paragraph 'car repair centers' would be a logical target kw for such a page so i would have thought it would be beneficial to create 2 versions of this page, 1 for US targeting US spelling & 1 for UK targeting UK spelling (centers vs centres), rather than 1x English to serve both UK & US audiences
Also I would have thought it would be useless showing a list of US car repair centers to UK visitors ?
Sorry for more questions, think that should be it now & thanks again
All Best
Dan