Drivers have been warned that it is planned to close the A272 at Buxted between September 23 and September 25.
East Sussex Highways is carrying out work to replace signs on the railway bridge and other applicable signs in advance of the bridge.
The road will be closed between C41 Coopers Green Road in an easterly direction to its junction with the A267 Heathfield Road.
Access to properties will be maintained where possible.
The advised diversion route is:
Via: A26 Uckfield Bypass – A22 Blackdown Roundabout to Halland – B2192 Halland to Blackboys – B2102 Blackboys to Beacon Down – B2239 Mayfield Flat – A267 Heathfield Road and vice versa.