The Google Maps team seems to be trying out different layouts and options for its bottom tabs. Most users have three tabs (Explore, Driving, Transit), in the US and other select countries you also have the For You tab, some users are starting to see another separate tab for the Map, and I just came across this other design with a combined Commute tab.
I was setting up directions on a friend's Android phone (running the latest stable 9.85.2 version) when I noticed something interesting. Instead of the usual Driving and Transit tabs, they had a combined Commute tab. Tapping it shows a new interface with "To work" or "To home" selections on the upper title bar, along with cards for the recommended and alternate routes on the bottom. A new overflow menu lets you quickly go to your commute settings, share your location or the directions, enable different layers (traffic, satellite, terrain), and change your route options.
New Commute tab with Home and Work selection on top and new overflow menu.
Since I've only seen this interface once on a friend's device, I wasn't able to check what it looks like when you use public transport as your preferred commute method, but it's probably similar to this with train/bus stations, departures, and ETAs.
This new UI is definitely more streamlined than the existing one; it dumps the sliding bottom menu and focuses on getting you where you need to go next as easily as possible. However, I'm not a fan of the top selection for Home/Work. With displays getting taller and taller, putting an option like this so far up means that you'll do some finger gymnastics if Maps doesn't guess your next destination correctly. The disappearance of the bottom sliding menu also means that you may lose some contextual driving destinations (your gym, school, or other place you often visit), plus the "Start driving" mode and navigation stats aren't immediately accessible anymore.
Current layout with separate tabs.
As always, this is a server-side test and one that doesn't appear to be widespread. None of us here can replicate it and we haven't received any other tip about it. If you have this new Commute tab and can provide more screenshots and details into how it works, especially if you use public transport, we'd appreciate to have a closer look at it.