But why the heck are you using LongLife servicing on a Golf GTI

??
And the stealer is being "economical with the truth", beacuse the "factory" do NOT set the servicing regime. The factory merely fill every sump with LongLife oil (irrespective of weather the car will be, or can be used for LongLife servicing).
The actual servicing regime is ONLY set by the local stealer who carries out the PDI (Pre-Delivery Inspection), before handing the keys over to the paying customer (and also on subsequent servicings).
The fact that your car "only" did 10k miles simply proves that your driving style is NOT suited to LongLife servicing. The fact they had then reset the SID at 10k without actually carrying out the servicing - will basically mean the oil was WAY beyond satisfactory quality, as the SID ECU was trying to process two conflicting readings (it has effectively been told the oil is new, but in reality, the oil is completely worn out, as proven by the previous "trigger" of the service due warning).
I really, really pull my hair out when people buy a high performance turbo charged engine, and then choose to run it on LongLife servicing regimes.
