Continuity and handoff void after latest updates on Mac

I'm afraid I don't have much more to offer than what Apple already provided in those Support documents. Here's another one that may help: Apple Support article: Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch.

Handoff and Continuity can be inscrutable—those features either work or they don't, and the protocols they use are opaque. As long as all your devices meet the many hardware / software requirements (and yours appear to), yet still aren't functioning the way you expect, then the only thing I have left to suggest is to Contact Support and see if they can offer some more productive guidance.

Refer to Use Continuity to work across Apple devices and Pick up where you left off with Handoff on Mac.

Otherwise, please describe what is not working in as much detail as you are able to provide.

Things to check.

1. Both devices need to have Bluetooth turned on
2. Both devices need to be signed in to the same iCloud account
3. Both devices need to be connected to the same Wi-Fi network (which of course means Wi-Fi also must be turned on)
4. Both devices need to support Handoff/Continuity (which if it used to work one can conclude is the case)

Therefore check 1 to 3 above.