Bamber was to share the #7 Ned Racing Ford Mustang with Andre Heimgartner in this year's Great Race; however, commitments in the United States will prevent the two-time 24 Hours of Le Mans winner from doing so.
Speaking with Speedcafe.com, team co-owner Stephen Grove confirmed the team has a replacement driver for Bamber, who will be announced in the coming days.
Click here to have your say on the state of Australian motorsport and go into the draw to win a Kincrome Tool Armour Workshop valued at $11,999.
“It's extremely disappointing because I know how good Earl is having raced with him before and having seen him race first-hand,” Grove explained.
“We've got a really exciting announcement who Andre's co-driver will be, which we'll confirm in the coming days.”
While Bamber will miss this year's crown jewel event, Grove said the team is planning to have him back in 2022.
“There's no question that we'll work with Earl to get him back next year hopefully and beyond,” said Grove.
“He's an extremely good talent. We'll definitely be bringing him back if all the dates align for 2022, no question.”
Bamber has just one start in the Bathurst 1000 to his name, finishing fifth with countryman Shane van Gisbergen in the 2018 edition.
Earlier this year Bamber set up his own Porsche Paynter Dixon Carrera Cup Australia team on the Gold Coast, dubbed Earl Bamber Motorsport.
His driver Matthew Payne is expected to replace Andre Heimgartner at Kelly Grove Racing in 2022.