Vortex Extension Tracker
Check whether your extension updates are available the easier way.
Tracking extensions for 4 versionsThis site is a simple utility to check the status of the current Vortex extensions file, useful for authors who want to check if their updated extension will be available to users.
What we refer to as the extensions file is a (massive) JSON file stored in the Vortex GitHub repository that stores all the details of the extensions available for Vortex. It's generated by the Vortex developers from the mods available on Nexus Mods. Extensions and updates won't actually be available to users until they're included in the extensions file, not just when they're available on Nexus Mods.
As for why it's needed, you'll have to bring that up with the Nexus/Vortex team but essentially amounts to them wanting to be able to vet the extensions available to users, including updates.
Short version: we don't know and we can't predict it. Usually, it's every 1-3 days.
It's a largely manual process run by the Vortex developers. Personal reservations aside, this just means that you'll have to be patient when releasing updates to your extension since they might not be made available for users for several days.