iMessage with Android and iPhone Users

I have been having this same exact problem. My son switched to Android 18 months ago, and he "unregistered" his phone number with Apple. Things were fine until last week (March 6, to be precise), then all of a sudden the group between myself, him and my wife will only send him iMessage texts and not SMS. This happened to both our phones at the same time. Jumped through Apple's hoops to make sure his phone number is no longer in their system (with a response it had already been removed); my wife and I have both turned iMessage off and on again. The only way we can use this conversation group is for both of us to switch off iMessage. Really a sad kind of work-around.

Texts straight to him, outside the group, are sent as SMS just fine.

If it's any help, the same conversation group in Message on my Yosemite iMac has dropped most of the SMS parts of the conversation, as well as on my iPad. Is there some sort of interference with Apple's new Continuity features?

I was hoping the iOS 8.2 release would fix this, but apparently the mandatory Watch app was more important.

This is the exact same thing that happens to me. I switched to an Android phone however my wife and I still have iPads and she uses an iPhone. I unregistered my number as apple requested. Normal Texting is fine however group messaging is messed up worse than ever. If I start a group msg with people on iPhones then it will switch to imessage and I will be left out of the conversation. Apparently everyone is thinking the iMessage bug is fixed but it is actually not fixed for group messaging and I do not hear anyone complaining about it. I love apple products but they just cannot get their services right. Or just release an iMessage app for android so I can get those group messages and I will be happy. But they need to do something.

Bump. I switched to Android and have been missing tons of group texts. I deregistered my phone number from iMessage. I have asked friends to start new group messages that will temporarily work as MMS but eventually switch back to iMessage. This is completely unacceptable, and it isn't right that Apple is effectively withholding messages from me.