2018 MacBook Pro randomly losing WiFi connection

My month-old Mac has randomly started dropping my WiFi connection without any notification. One moment it's working fine, the next I'm offline. According to the WiFi dropdown in the menubar, my machine is behaving as if I had clicked to disconnect from the network; WiFi is on but not connected, all networks that should be in the list of nearby networks are there, and clicking on my network connects back up in under a second and I'm back to working again online... until it drops again anywhere from ten minutes to a few hours later.

This issue started almost immediately after installing "macOS High Sierra 10.13.6 Supplemental Update 2 for MacBook Pro (2018)" from the Mac App Store and is affecting me on any WiFi network I connect to now if I'm connected long enough. It's usually just a minor inconvenience, but if it went down at just the wrong time it could cause serious issues with what I use it for. My 2011 MacBook Pro, also running macOS 10.13.6 but without the update specific to the 2018 model, doesn't have this issue... nor does any other device in the house, including a 2014 MacBook Pro, two 2007 MacBooks, and a 2009 iMac which are also all on the latest versions of macOS that they support. (Same for all the iPhones, iPads, and Apple TVs in the home) It looks like this bug is reserved for those with the latest and greatest portable Macs, so I'm out of luck until a fix comes around.

Does anyone have any ideas as to what may be causing this? I'm pretty sure it's an issue with the recent update; my Mac doesn't have a whole lot on it yet besides Apple apps and Adobe Creative Cloud software, and I don't browse anywhere or download anything from anywhere that could have given me anything unpleasant on my system. I basically treat this thing like a baby, so there seriously shouldn't be any issues with it already. My MacBook Pro and AirPort Extreme are both on the latest software version they have available, and I've troubleshooted both devices.