iPhone 5 iOS 8.4 messages missing after hard reboot

My messages (all SMS and iMessage) are missing after hard rebooting my iPhone 5 on iOS 8.4. In the Usage Settings, they still show up as taking 4.2gb on the device and are still available on my MBP and iPad which are all up to date but every conversation thread is missing.

Is there any way to recover them outside of restoring from backup which was about a month ago?