The Windows 10 build 19041 that's current in the Insider Slow ring is allegedly the final version [for now] that will be generally available this spring via Windows Update. It's supposed to be the version that Microsoft signed off on as RTM [Release To Manufacturing] that's available for the companies making Windows devices & software to start testing & incorporating into new products. You can of course do the same, making sure that there's nothing in this new version that breaks the stuff you have, or just to take advantage of new features.
The official way to get it is to sign up as an Insider [if you are not already], which just takes a regular Microsoft account [the one tied to the copy of win10 you want to update], then go to Settings -> Update & Security -> Windows Insider Program, & set up that copy of Windows for the Slow ring. The update to 19041 should then become available in Windows Update. You may want to turn that off before the next version update hits the Slow ring.
There's also a chance that Microsoft will release 19041 ISOs for the Insider program. Currently the latest is an earlier build, and historically Microsoft's record is spotty in this regard -- the next Insider ISO that's released may be 19041, or it may be a newer beta of a future build. You'll need to be signed up for the Insider program, and sign into the download page.
You can easily find several unofficial ISOs available for download using Google, assuming that you trust that download to be free of malware etc., or you can use a work-a-round to create your own ISO...
Microsoft packages everything needed to install Windows in a single .wim file that's included on the Windows setup discs that are used to create Windows ISOs. You can take that ISO & burn it to a DVD, or use something like the free Rufus to put it on a bootable USB stick. You can also mount that ISO, navigate to the mounted ISO in Windows Explorer, then run setup to update that copy of Windows.
When you upgraded Windows 10 via Windows Update, Microsoft originally had you download that entire .wim file, only it was packaged in an encrypted .wim called an ESD. But, you don't need every single file in that complete .wim package, since it includes everything for several different devices and options. To reduce the size of the download and at the same time require less storage space, Microsoft now splits that complete .wim file into several smaller ones, so Windows Update only downloads what you need, using multiple ESD files. You can visit uupdump[.]ml/ to get a script that will download the files needed to make up a complete .wim, and assemble an ISO using that .wim file.
Following the directions on that site, you tell it what version of Windows you want, and it generates the script that you download. You'll also need to follow a link on the page to download a small file called aria2. Unzip the script, & unzip the aria download, then put the single aria file in the same folder as the script. When you double click the script it opens a command prompt window & does everything you need -- when you're done you'll have an ISO in that same folder as the script.
I've used a similar tool in the past [which no longer works] and the ISO it produced worked, but not as well as the official ISO. But that was only one time, so I can't begin to predict any sort of success rate.
DO NOTE that at least once before Microsoft reached RTM status with a build of Windows 10, only to find previously undetected problems, so they pulled that RTM & eventually released a new build to GA [General Availability]. Assuming that reports are correct & build 19041 is the Spring 2020 RTM, that could change between now & then.
