When you boot or restart your VCS it will check to see if there is a system or BIOS update, and if one is available, it will download and install automatically.
You must wait for this process to complete before logging into your profile.
You can check and see if an update is available by navigating to SYSTEMS > GENERAL SETTINGS > SYSTEM UPDATES.
If an update is available, you can continue to use your VCS while the update downloads. The update will be applied when you next power cycle the VCS.