This month’s Mobil 1 Twelve Hours of Sebring is unlikely to feature a capacity grid, following at least two withdrawals from the event this week.

An updated entry list for the second round of the TUDOR United SportsCar Championship was released on Thursday, which confirmed the withdrawal of the No. 97 Aston Martin Racing Vantage in the GT Le Mans class.

The factory entry, which was driven by Darren Turner, Stefan Muecke, Pedro Lamy, Richie Stanaway and Paul Dalla Lana at the season-opening Rolex 24 at Daytona in January, appeared on the initial Sebring entry list with to-be-announced drivers but has since been pulled.

AMR team principal John Gaw told Sportscar365 last month they had yet to confirm their prospective program for the Tequila Patron North American Endurance Cup and had been waiting on what Balance of Performance changes, if any, would be made to the V8-powered car.

IMSA later confirmed the GTE-spec Vantage would be given a 20kg weight break and 0.3mm increase in air restrictor size for Sebring.

AMR’s withdrawal reduces the GTLM field to 11 entries.

A further entry change comes in the GT Daytona class, with the Rolex 24 class-winning Level 5 Motorsports squad confirming its exit from the series this week.

While both Level 5 Ferrari 458 Italia GT3s still remain on the official entry list, at least one is expected to be formally withdrawn, with another team understood to be in the stages of finalizing an entry with drivers Bill Sweedler and Townsend Bell for the remainder of the season.

Sweedler and Bell were part of Level 5’s class-winning effort at Daytona and would retain the drivers’ championship lead heading into Sebring.

Should a deal be done to keep one of the Ferraris on track, it would result in a reduced entry of 66 cars for the race, two fewer than the race’s maximum capacity.

It’s understood there are no teams remaining on the reserve list, which was published in December.