Hello Dr Haddad,
Got my 2,7D S Type in February, Whilst driving to Spain the amber, restricted performance light came on, just after setting off mid France, early morning. Stopped the car, waited 5 min's, then re-started. Light off but came on again, couple min's later. Stopped, started and all was OK.
This happened for the next few mornings, but since then all ok. All the times it happened it was raining? Since then, both in Spain and here have had no rain.
On getting back home had the car diagnostically checked and my fault showed up as an EGR valve, which can be pricy Luckily for me the car had 3 months warranty, so it goes in for repair in early June.
Hope yours turned out to be something simple.
Happy driving.
Alan.