And a recipe for failure. All 100% of their staff needs to be moved off of Windows at the same time.

A few years ago, IBM tried to move everyone to LibreOffice from M/S Office. It failed, the reason why was top level execs and some others were allowed to stay on M/S Office. As time went on, M/S Windows became a Status Symbol. So people went begging and as time went on exceptions were granted. A few even went so far as to buy their own copy, which was allowed.

After 8 months IBM gave up. If you want things like this to succeed, you must be 100% in.