Hello, When I upgraded to Yosemite several months back I was able to both receive and send outgoing cellular calls via my early 2011 MBP and my iPhone 5. I noticed ~1 month ago that this was no longer working (or sometimes I could receive calls on the MBP but never send outgoing calls), and upon further investigation it appears the "iPhone Cellular Calls" option is missing from my MBP's FaceTime settings. My iPhone and MBP are both signed in with the same Apple ID into iCloud. FaceTime is activated with both my Apple ID and phone number both on the iPhone and the MBP. The iPhone Cellular Calls option is switched on in the iPhone's settings. Both devices are on the same WiFi network. I have also updated to 10.10.3 and 8.3 today. I meet the requirements listed here https://support.apple.com/en-us/HT204689 for phone calling. On other posts online it seemed like the only fix for users was to restart and the option came back, but I have had no luck Has anyone else been able to fix this?