For HENkakuís 3 year anniversary, Yifan Lu has something in store as well although it isnít in the form of some massive release but of an interesting write-up. This write-up, which was originally written in January 2019 was intended to be published when somebody found the same vulnerability in 0x50002 service that it discuses.
If you want some interesting reading material, then make sure to read Yifan Luís write up on the first F00D exploit!

Unfortunately, this didnít happen even though there were various hints on the HENkaku Wiki that the service buggy probably due to lack of interest in hacking the obscure F00D processor. As usual with Yifan Luís blog posts, itís pretty well written and the gist of it can be grasped by anyone with limited knowledge of computer security so if youíre into learning how vulnerabilities/exploit work, you should surely give it a read when you donít have much on your hands!

On the other hand, Xerpi has recently posted build instructions for generating a Linux kernel to boot with his PSVita Linux Loader software. Unfortunately, Vita Linux hasnít seen much progress after the initial groundwork done in December of last year but Xerpiís known for making the seemingly impossible possible, which was the case with udcd_uvc so work on Vita Linux might continue someday. The main purpose of these build instructions is probably to help more experienced developers to get working on improving the PSVita more quickly but arenít very useful for regular users as a precompiled Linux kernel can already be downloaded. Itís important to note that Vita Linux doesnít support the PSVitaís display so if you boot it, youíll just see a black screen; output is currently available via UART0 which is a debug interface that requires soldering to use. Thanks for the heads-up on this @TheheroGAC