Hey Gianluca,
Thanks for that very detailed response, I have a few extra questions:
1. You say using the canonical tag vs 301 redirects is risky: Is that to say, having this solution in place even for a few weeks whilst we plan and implement a better solution could have negative effects for us? If so, what sort of negative effects could we incur?
Before the next question, I'd like to give you a little more background; our site is like an online shop, but refers you to other retailers to complete your purchase. We have department pages, a few content pages like "contact" and "terms", a search listing page, a homepage, and a brands page.
- Our department pages have links to related articles, brands and products and I expect these will be very different between the two sites.
- We have a search page, but the data changes daily and the data will be drastically different between the two sites at any one time since the products will be from retailers local to the US/UK
- Our brands page is mostly generated and so can change slightly per day but is likely to be very similar accross the two sites.
- Our static pages will likely start of identical and start to evolve independently (if at all) over a very long period.
2. Keeping all of this in mind, I am not sure if hreflang is still appropriate because it is not going to be the same content translated, but instead similar pages with uniquely tailored content based on its location. What are your thoughts on this? Am I misinterpreting or being to strict in my understanding of what hreflang should be used for?
3. in the above response, you wrote: "you should preview a dilution of PageRank because of the internal linking toward the new USA version" - Is this to say we will start to lose page rank on the UK site as people start to visit the USA site? I just wanted to be clear about what this means, because I am seeing words such as "preview", "dilution" and "internal-linking" which sound like they may or may not be SEO related terms.
4. Finally, I have read conflicting articles about the effectiveness of adding a cache expiry to 301 redirects. Could this be effective for our scenario? Will Google interpret it as a temporary redirect? Will user browsers really expire the 301 when we specify?
Thanks for your advice,
Dipun