Guido alluded to it a few posts ago, but apparently Gus is using the Rymans (neighbors) as lookouts and using their home as a control/command center to monitor his home. Somehow he managed to excavate a massive tunnel between the two properties without the HOA noticing.
What threw me off during the cold open was that I thought the male on the Bike was Saul and that the scene was some sort of time jump. That actor/character has a very similar speech cadence to Odenkirk.
Something I also missed during the first viewing was they guy who Gus passed in the tunnel is dressed exactly like Gus. Apparently Lalo isn’t the only one who is utilizing a body double.