From a notification by Keir Highways here:

Kier Highways, on behalf of Highways England, will be carrying out work to resurface a section of the A3 southbound carriageway between the Canadian War Memorial and Liphook junction, to ensure the network remains in a safe condition for our customers.

The work is currently scheduled to take place over four nights starting on Tuesday 7 May 2019.

TRAVEL: Portsmouth Road between Bramshott Chase and the A3 will be closed from 8am today for resurfacing works…as it runs parallel with the A3. Traffic will be diverted through Grayshott village. pic.twitter.com/zvgLxuPB2k— BBC Surrey (@BBCSurrey) April 26, 2019

For the safety of our workforce and customers we will be closing the A3 southbound carriageway between the A31 Hog’s Back and Liphook, with a signed diversion in place from the Hogs Back, west along the A31, then south on the A325 to Longmoor.

Access will be maintained along the A3 southbound carriageway for villages between the Hogs Back and Thursley, and for emergency service vehicles on blue light calls.

Please be aware that these works have been carefully programmed but are subject to change due to weather conditions or unforeseen circumstances – please check the yellow signs placed in advance at the junction for confirmation of the closures dates/timings.

We would like to apologise in advance for any inconvenience or disruption caused during our work; if you have any questions, or if you’d like to know about our work please contact us on 0300 123 5000 or email info@highwaysengland.co.uk