I went on holiday to Germany for one week and left the VPN to my home network on. When I came back, I had to wait two weeks before Google believed that I was no longer in Germany. The language settings were easy to change, but the "this content is not available in your country" message that Youtube seems to default to in Germany was rather annoying.

Google was actually reasonably quick. I've had to deal with GeoIP providers marking an eastern European IPv4 block sold to a Dutch ISP which took months, and I think a few services still think that block belongs to some Ukranian ISP.

If you update your HE information, the GeoIP databases will update too, but it can take a while. Every site admin that manually downloads their GeoIP database needs to update theirs before you can visit your site.

This is also a lesson to web admins: if you're going to use GeoIP databases for country blacklisting, update them often. Unless you've containered yourself to hell, your OS distro probably automatically distributes databases in some form.

I also experienced this in the US. My service provider does not provide IPv6, so I used HE's tunnels. Even though it's v4 under the hood, I wanted to see what the illusion of v6 felt like.

I turned it off after a few days because of the same side-effects that you mention.

I am surprised. I guess, even with an an address space so wide that you can almost randomly choose one that is free, websites are still able to identify certain types of actors. I'd imagine that the heuristic is more of an allowlist in IPv6, versus a blocklist in IPv4.

I think if you update your address and country in your HE account it will also update the geolocation of your ipv6 range, although i do not know how long it takes, especially since it is dependent on the different geolocation services themselves

Nope, it is behavior-based, this address range doesn't have any special geolocation, it is assigned to HE and it's all.