It's been working for me since Beta 2 on iPhone and OSX.
I found that by specifically pairing my phone and mac via bluetooth this caused it to STOP working. Perhaps this has something to do with it using BT LE, but I genuinely don't know.
One thing I did notice; I sign into my iCloud account via my gmail address. I also have a @icloud.com and @me.com on the same Apple account. It didn't work when devices were signed in via @gmail.com, but when I switched them all around to @icloud.com it started working. But like I say; the two are not paired directly as you normally would with Bluetooth it just....works.
BTW: You say you're on a 2010 MBP? If so I don't believe your mac will ever support continuity!
See the following:
https://www.macrumors.com/2014/06/17/yosemite-handoff-bluetooth-le/
Go to About this Mac > System Report and look for " Continuity Supported:" under the "bluetooth" section. If it says no; then I expect this will be your problem.... (although theres some uncertainty as to if this applies to Continuity, handoff or both including calling at this point in time! It works for some not for others....)