option, as per https://aka.ms/msvc/preview

To install an older in-support release, you need to run the Visual Studio installer, switch to the 'Individual Components' tab, and find the 14.5* toolset to install. If you are on the Insiders channel, only had the default MSVC toolset chosen, and recently upgraded, you'll see that your 14.50 toolset was replaced with 14.51... add it back in the 'Individual Components' tab.

# Why are we doing this?

The biggest benefit of the new model is to vastly shorten the distance between MSVC features and folks using them in a Preview. Folks on the MSVC development team can make a change which ships in the next week or so. This timeframe used to be months, but has now shortened to just a week. Not all C++ users want this, so MSVC Previews are an optional installation component.

Most of the other reasons are called out in https://aka.ms/msvc/lifecycle:

The MSVC team is leaning into the Visual Studio release cadence
We are aligning our long-term-servicing releases with those of .NET
Servicing 10+ year old compilers has become increasingly complex.

# tl;dr, and what should folks do?

If you want the bleeding edge tools, stay on the Visual Studio Insiders channel and install the 'MSVC Build Tools for <arch> (Preview)' option. Please give us feedback by reporting bugs on https://developercommunity.visualstudio.com/ or through the Visual Studio IDE itself.
If you want stable tools that only update every 6 months, stick with the Visual Studio Stable channel, and use the default C++ tools.
Want to get a head start on the every-6-months update? Look for our release candidate blog posts (https://devblogs.microsoft.com/cppblog/msvc-build-tools-version-14-51-release-candidate-now-available/), and use Visual Studio Insiders with the default C++ options.

Thanks for reading.

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