The Rail Accident Investigation Branch wants drivers to not make assumptions on routes.
A fault with overhead wires is blocking the line towards Colchester, says Greater Anglia.
East-West Rail says the new entrance at Cambridge railway station could be open by the mid-2030s.
East West Rail has released updated plans for the London Road Level Crossing ahead of a consultation.
The line could cost £100bn but HS2 says it is spearheading wider regeneration in the West Midlands.
A rail company says four trains an hour will stop at a station there "by the early 2030s".
The Rail Accident Investigation Branch looks into a train coming off the track last summer.
A brother and sister who live nearby describe hearing noise at night "that is so abrupt and loud".
National Rail says services are beginning to get back to normal but some delays could remain.
