Yes it did. RF (now a sim instructor and has a child flying for CX) did exactly that. It was a response to a coordinated resignation by a number of STC's.
It would never have stood up in a regular court of law, but there are 2 things to remember here:
1. CX is a massive employer in Hong Kong and the courts kowtow to CX's whims and desires.
2. Who runs out if money first? (The same "invitation" made to the FTA instructors). If you don't know the ongoing saga of the FTA issue, ask around.