Yes, i have successfuly tested it. I get a public IPv6 address on mobile network. I can access services on RUT950 from the IPv6 internet (eg i can establish SSH2 connection using DNS AAAA record).
Still have some issues. I am interested to share the information with you and ask some support questions.
The mobile network operator development team suggested that the wwan0 hardware mac address changes and that this is the reason me (the end user) is not getting STATIC public IPv6 address.
Any way to evercome that? Can i "set" the MAC address for the mobile network as "fixed" (i don't want it to change on every reboot). That way - by theory i will get a static pubblic IPv6 address on mobile network.
(Croatia, Hrvatski Telekom that is part of Deutsche Telekom - closed test APN only)