The East Coast line will be closed between Northallerton and Newcastle on these two weekends for engineering work, affecting trains to and from Scotland.
A limited service will divert via the County Durham Coast adding 1 hour to journey times.
Other services will be replaced by coach (bus) between York and Newcastle on the 1st weekend and York and Durham on the 2nd weekend. That adds 90 minutes onto the journey time. It will normally be fastest to use the diverted train service.