Err, i prefer you tell me what to look for really and what experiences your team has solving an issue like this?
as surely something like this has been encountered before?.... please use your teams experience to help you, giving you access to a clients website for something, that should have some basic steps to try first or look for first, seems like over reach to me..
AND I CAN SAVE TIME WATING FOR ANSWERS, BY CONTINUING TO HUNT AND TRY AND FIND A SOLUTION MYSELF !!. THATS ME SAVING YOUR VAULABLE TIME AS WELL RIGHT? THE SITE IS RUNNING MIRACULOUSLY WELL ON J5.xx AS IT IS RIGHT NOW. Would I like to upgrade like the rest of course.
This is a sigificant clients e-commece website ..with nothing on it except your page builder and all its add-ons that comes with it..
Ive been doing regular backups of this site btw since i encoutered this issue and alwwys back up before any upgrade, so no problem there, but you should not need to get access for every question you get. IMHO of course.
Regards