IPv6 connection issues

[pkoryzna]

hi there, seems to me like there are some IPv6 reachability issues. There is an AAAA record:

;; ANSWER SECTION:
v6.bvg.transport.rest.  3513    IN  CNAME   thuya.jannisr.de.
thuya.jannisr.de.   82713   IN  AAAA    2a01:4f8:c012:91b7::

but that seems to not be reachable from my network:

% curl -6 -v https://v6.bvg.transport.rest/
* processing: https://v6.bvg.transport.rest/
*   Trying [2a01:4f8:c012:91b7::]:443...
* connect to 2a01:4f8:c012:91b7:: port 443 failed: Operation timed out
* Failed to connect to v6.bvg.transport.rest port 443 after 75008 ms: Couldn't connect to server
* Closing connection
curl: (28) Failed to connect to v6.bvg.transport.rest port 443 after 75008 ms: Couldn't connect to server

just in case it was something misconfigured on my side, I also tried on this website and it too cannot connect:

https://ready.chair6.net/?url=https%3A%2F%2Fv6.bvg.transport.rest%2F

this is causing a bit of a problem since some environments I am using default to v6 and time out without trying v4 (micropython)

let me know if you need more details!