For some users, software updates are a thing that may or may not bring in some fun new features. For others, they're a necessity which brings in fixes and improvements to the system, making them all the more of a useful thing to have pop up on your device. For Project Fi users who purchased their Nexus 6 device from Project Fi, a small update is starting to come through today (announced yesterday) which should help to improve a couple of things. It weighs in at 92MB which is by no means going to take a while to download and install, and given the size it obviously isn't bringing in loads of new functions and pretty new UI changes.
If you purchased your Nexus 6 from Project Fi then your device would have been shipped with Android Lollipop build LVY47H, and if your device is currently running that build then you should end up seeing the software update alert come through to your phone sometime between now and the weekend. It is also worth noting that this is the update for Android 5.1.1, which pushes Project Fi Nexus 6 owners up to build LVY48C, and will bring in some bug fixes which are intended to help fix the connectivity issues some users have been experiencing in certain parts of the U.S., like Arizona and Seattle for example which were stated by Googler Justine Rivero in the G+ announcement about this software push yesterday. This of course alongside the handful of other changes which come with Android 5.1.1.
For those that use Project Fi, this is most likely a software build which should be of importance, but if you haven't been experiencing any connectivity issues then there probably is no rush to move to this software and it'll end up rolling out to all compatible devices in due time. For those that have the Project Fi Nexus 6 and have been seeing issues but haven't yet seen the software update come through over the air, it's entirely possible to manually flash the OTA software build, but it's only recommended if you're familiar with the process of doing such things. If that's the case, you can grab the OTA software for LVY48C here and flash away.