Where did you buy it from Dave, there may be a few numbers on the board which the site experts could use to determine it's age etc. I had a line fail problem on a Abacus not so long back solved it by linking up to the telephone system. It looks like a unit that has been removed from a property if this is anything to go by:-
"...Also (on my classic it used to say something like Manager Reset Required) now its saying "Call Alarm Co. Quote Code xxxxx....".
So, it's obviously an ADT panel..we don't know it's age..Don't know where it was bought..Don't know if it's stolen and so on.
Well done though for diving in at the deep end with ethernet, iro's and so on using a panel which often dumbfounds the common or garden installer.
Give us some history... Have you bench tested the panel (usually the first job), where it's bought from etc...