Disco 4 (LR4) Long Shot....but I'll ask anyway

So tomorrow I'm trading in my LR4 for a nice new LR5. I'm looking for my service history but can't find the details of the last service I had (which was done by a non-LR service agent - hence not digitally recorded). Because I'm useless at keeping documentation I don't have the original receipts etc and can't find a date with which to go back and ask the garage to pull out their copies of the work (they are still using paper systems!). The service indicator obviously got reset so I must have had a service done - does anyone know if, somewhere in LR engine management system, it date stamps the indicator reset so that the LR dealer diagnostic tools can see when the last service was done? Probably not, although it would make sense to do so to me.