recovery of iPhone Messages (texts) 6-12 months old?

you will need to check and see what all your icloud has backed up or not backed up. pretty much only way to try and retrieve them if they were deleted..down side is if your phone has done any other back ups since then they might be lost for good and covered over by the most recent phone back up.

if its for a legal matter then the only other way would be by court order to TMO but thats if you are wanting the actual text content...if its just to show the amount of times you were contacted by a specific number then that can be pulled up through your billing.