spl4tt Pixel 10, Pixel 10 Pro and Pixel 10 Pro XL were on a mix of Android 16 with some Android 16 QPR1 for the initial release. Their day 1 update in August was full Android 16 QPR1. September was the official release of Android 16 QPR1 but they got it less than a week earlier in August, then got another update in September. Pixel 10 Pro Fold launched in October and only has full Android 16 QPR1 releases available.
It's technically possible for us to do something similar to what we are for the 3 Pixel 10 devices launched before the Pixel 10 Pro Fold. We've been working on it and that's nearing completion, so we can publish experimental releases for the first 3 of the devices before Android 16 QPR1 is pushed to AOSP, but not the Pixel 10 Pro Fold. However, it's not a good situation as a whole. We also have a lot to deal with due to the lack of Android 16 QPR1 tags and also the new security preview releases we're providing, among many other things. Adding 4 new devices is not something that's easy to fit in right now even if they had pushed the releases to AOSP as has always been done before.