The emergency diversion route will still be in use at the Rest and Be Thankful in Argyll at the weekend.
Three landslides hit the A83 Tarbert to Campbeltown road at the Rest following extremely heavy rain on Tuesday.
Several thousand vehicles have made use of the Old Military Road (OMR)diversion route as the clear-up continues.
The OMR is more than 26 miles or 38 minutes shorter than the alternative diversion route and saves road users, including hauliers, both time and fuel costs.
The majority of the debris has now been cleared from the A83 and all that remains are some large boulders on the hillside. They have to be secured or broken-up before the road is safe to use.
Thick fog has hampered work at the top of the hill and the weather forecast suggests this is expected to persist until Saturday.
As a result the Old Military Road Diversion will continue to be in use at the weekend.
Transport Scotland’s Head of Network Maintenance, Graham Edmond said: “People traveling through Argyll and Bute have continued to use the Old Military Road diversion route successfully. It is much shorter than the traditional diversion and it brings time and fuel savings.
“Everything possible is being done to get the debris from this landslide clear-up as efficiently and safely as possible.
“So far, 2000 tonnes of rock and mud has been removed with specialist equipment brought in from across the country. Some of the boulders have been extremely large and have had to be broken up before they can be transported.
“The safety of our staff and the traveling public is our top priority and with visibility being very poor today we couldn’t send our teams up the hillside and expose them to risk of injury.
“I would like to thank drivers in the area for the patience they have shown over the last few days and I want to reassure them that everything possible is being done to rectify the situation. This landslide is the largest that we have had on record and that brings enormous challenges but we are looking at every possible solution that will help us get the road network back to normal operation.”
Chair of the A83 Marketing Group, Mike Story said: “The area has proven as resilient as the debris nets on the Rest and be Thankful held back tonnes of debris, including car sized boulders.”