I think a year or two may be optimistic. One can only assume that if you start using class E then you've already used up all of 10/8. So the only option is to m

I think a year or two may be optimistic. One can only assume that if you start using class E then you've already used up all of 10/8. So the only option is to move to IPv6. I don't know AWS internals, but they may need to do hardware revisions they need to roll out to switch ASICs, not to mention millions of lines of code. And the addresses will be "kinda broken" everywhere, basically forever. So AWS wouldn't even get the blame. So there's no incentive for them to have a moon landing program costing them many billions, throwing away hardware before they otherwise would. Of course it is 2022, so I would hope that AWS's current production hardware is IPv6 ready at equal pps, FIB size, and features, but I wouldn't be surprised if not. But the software should not be underestimated. That IPv4 address in a database, stored as 32bit integer, is not exactly trivial to extend on disk and by every single reader and writer. Nobody will want these second class addresses, not on the client nor the server, so who are they for? (on the public Internet, that is. They could be used as 100.64.0.0/10)