FreePBX 13 to SNG7 update breaks calling

As reported in QA-956. When updating a Freepbx 13 Distro system to SNG7 via the instructions in Wiki https://wiki.freepbx.org/display/PPS/Upgrading+from+FreePBX+10.13.66+to+SNG7

Steps to recreate:
Install 10.13.66-21 from FreePBX-10.13.66-21-x86_64-Full-1503108270.iso
Create two pjsip extensions
Register Phones via EPM
Confirm Calling works between extensions.

Update to SNG7 via the instructions in Wiki https://wiki.freepbx.org/display/PPS/Upgrading+from+FreePBX+10.13.66+to+SNG7

Calls will fail due to missing device entres in ASTDB

The ASTDB gets nuked and causes calling to fail unless you manually resubmit every extension.

The update scripts do a downgrade of asterisk (in my case from 13.22.0 to 13.17.0 guessing this it due to asterisk versions available in the anaconda repo), which is more of a rip and replace via yum shell script /tmp/asterisk13_packages.yum (attached).

 
 
Log snip from /var/log/sngupdate
 

 
{{# grep "enforcing package installation 'asterisk13" /var/log/sngupdate
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-core.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-addons-core.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-addons-mysql.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-addons-bluetooth.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-doc.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-addons-ooh323.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-voicemail.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-dahdi.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-flite.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-addons.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-odbc.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-resample.x86_64'
HOOK-pkgdowngrades: INFO: DOWNGRADE: enforcing package installation 'asterisk13-curl.x86_64'}}