Jaguar Challenge 2018 dates are:
Donington4th - 6th May
Silverstone16th - 17th June
Le Mans Classic 6th - 8th July
Oulton Park 25th - 27th August
Spa Six Hours 14th - 16th September
According to HSCC the Le Mans round is not officially part of the not-officially-a-championship series. Details, such as they are, are here
https://hscc.org.uk/event/le-mans-cl...8th-july-2018/
Can it really be 2 years since my E-type last ran?