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#11
MiniTool Partition Wizard is much better for doing what you want to with your partitions than built-in Windows disk management:
Best Free Partition Manager for Windows | MiniTool Partition Free
If you let Windows update install the Redstone update, it will be pretty much like a cumulative update. It will keep all your files and settings, but it will produce a windows.old folder and give the options to rollback in the advanced troubleshooting menu.
If you run the Redstone update from an ISO file (either created from the update install.esd file or with the Media Creation Tool), you will get all the options you have with a normal Windows 10 ISO file - clean install if you create a bootable media from the ISO file - or the usual system upgrade options if you run setup.exe from within your existing Windows.