You're basically doing carrier grade NAT for that, the same thing that is apparently tooootallly acceptable to the ipv6 people for their big success story: mobile.
The only success story of ipv6 leads us to the solution: backbone-level CGNAT and other hacks, then impose the economic cost on IPV4-only carriers and endusers.
The only success story of ipv6 leads us to the solution: backbone-level CGNAT and other hacks, then impose the economic cost on IPV4-only carriers and endusers.