The Central line is suspended all weekend between Loughton and Woodford due to engineering works.
The route is also suspended on the 'loop' between Woodford and Hainault.
Replacement buses are in operation.
The first bus service stops at Woodford, Roding Valley, Buckhurst Hill and Loughton.
The second runs between Woodford, Roding Valley, Chigwell, Grange Hill and Hainault.