Blocking / Reporting Spam Texts
It's undoubtedly just a coincidence, but as soon as I upgraded to IOS 10, I began receiving spam texts, which I never got before.
A little Googling showed how to block spam texts in IOS 10 (it's a little different than before): http://www.addictivetips.com/ios/how-to-block-a-number-from-messaging-you-in-ios -10/
However, the method for reporting spam texts to Apple now appears to require that “Filter Unknown Senders” be turned on: http://recomhub.com/blog/how-to-report-imessage-spam-on-ios-10-for-iphone-and-ip ad/
I really don't want to leave Filter Unknown Senders on all the time, so my question is, does the filter run (or can you make it run) on texts that have already been received? That is, if I turn on the filter, will all the texts already received that are from senders not in my Contacts be moved into the "Unknown Senders" category from which I can mark a message as spam and report it as junk?
If not, is there any other way to mark/report an already-received text as spam?
iPhone 5s, iOS 10.0.2