It would seem Apple's latest updates for some of their OS lines would not stick to Apple's own specifications regairding their Private Relay feature.
Quoting from Apple's docs at
Prepare Your Network or Web Server for iCloud Private Relay - Apple Developer:
Those are the domains that are handled by Pi-hole's BLOCK_ICLOUD_PR.
Apple seems to have introduced a different or additional option and/or label 'Limit IP Address Tracking' that does not seem to honor those DNS request answers as specified.
See Safari won't finish loading certain sites after iOS 15.5 / MacOS 12.4 upgrade for a detailed discussion.
In order to be properly addressed, this should be raised with Apple's support, really.