NVIDIA have release two new drivers over the last day! An update to their Vulkan beta driver as well as a new stable driver update for everyone.
Firstly their Vulkan beta driver, the special branch they use for testing new Vulkan API bits and more, has been rebased onto 435.17. They also mentioned that 8-bit integer support has been added to the VK_NV_cooperative_matrix extension and performance improvements have been taken from the 435.17 series.
Additionally, the bigger one here is the new 435.21 stable driver. This is almost the same as the recent beta release of 435.17, which is the update that finally brings in support for PRIME render offload. However, they also noted one extra bug fix over the beta "Fixed a bug that caused the X server to crash when using HardDPMS with an NVIDIA-driven GPU Screen.".
The 435.21 driver is part of their "Short Lived" series as opposed to the current "Long Lived" series at 430.40.
Confused on the difference? Here's what NVIDIA themselves said about it (source):
Any given release branch is either long-lived or short-lived. The difference is in how long the branch is maintained and how many releases made from each branch. A short-lived branch typically has only one or two (non-beta) releases, while long-lived branches will have several.