Railadvent has updated the list:
https://www.railadvent.co.uk/2020/03...-covid-19.html
This now includes main line cancellations from UK Railtours, Belmond British Pullman, Saphos Trains, Statesman Rail, Railway Touring Co., Vintage Trains, Hastings Diesels Ltd. & the A1 Locomotive Trust's Tornado Tours.
Complete closures at Didcot, Dean Forest, Llangollen, Bala Lake, Churnet Valley, Severn Valley, Mid Norfolk, Pontypool & Blaenavon Railway, Gwili Railway, Gloucestershire Warwickshire Railway, Mangapps Railway Museum, the NRM & Locomotion at Shildon, Romney Hythe & Dymchurch, Statfold Barn, Swindon & Cricklade Railway and Hampton & Kempton Waterworks Railway.
Other railways have cancelled events or are running a reduced train service.
Tony