I think they've made a change to where SMS handoff is handled. With my phone (ios 8.1b2) having both Wifi and Bluetooth off, SMS messages are arriving on my mac running the latest public yosemite beta. Seems like they've set it up so that SMS are mirrored on iCloud rather than being relayed via the iPhone. That, or the phones wifi/BT is on without me knowing it or all my 2 factor auth sources have picked up the ability to send over iMessage. Anyone else seeing this happen?