The builds are there: https://launchpad.net/ubuntu/+source/php8.5/8.5.9-0ubuntu2.1

https://launchpad.net/ubuntu/+source/php8.3/8.3.6-0ubuntu0.2...

https://launchpad.net/ubuntu/+source/php8.1/8.1.2-1ubuntu2.2...

but nothing shipped yet by their mirrors, unlike debian.