Messages Thread Consolidation (iOS 10 Edition)

[Branch]

Pretty much just this question, for iOS 10, since it still applies.

https://forums.macrumors.com/threads/does-messages-consolidate-conversations-in-ios-8.1762454/

A lot of us probably have multiple iMessage conversations open for the same person on our iOS devices, since there are at least four possibilities for everyone:
Your Phone Number - Their Phone Number
Your Phone Number - Their Apple ID
Your Apple ID - Their Phone Number
Your Apple ID - Their Apple ID

It's further complicated when an Apple ID has more than one email address associated with it.

OS X Mavericks's Yosemite's El Capitan's Sierra's Messages app addressed this by consolidating multiple Messages conversations into a single thread, if the different Apple IDs and phone numbers were associated with the same contact.

Does iOS 8 10 do a similar consolidation?

Also, kinda off topic: any improvements to Field Test mode in iOS 10? Namely it finally being optimized for iPhone 5, much less iPhone 6 & 6+? Or anything else?