I created a bootable flash drive with 3.5.79/8 (however the versioning works) and just imaged it. Not sure how long this will stay up. Just download the raw image file here and use something like win32diskimager to write it to a flash drive. Should be fully bootable/updated as of now. Minus the linux diagnostics part, which I cannot find a working download for.

tested it with 2 different flash drives, usbc and usba, 2.0 & 3.1, didn't have an issue booting it ever. Should ideally make the process a bit simpler/quicker.

Code:
https://archive.org/details/lenovo-u-1-tool-
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