Percat, who turned 33 on Tuesday, has been linked to the Walkinshaw squad, the team that first signed him as a teenager in 2007.
"Percat will fit back in somewhere, and that means another opening will need to be created," Tander said.
"There’s lots of drivers that are off-contract and working out where they’ll go.
Percat confirmed he will depart BJR at the end of 2021
"A lot of the chat around Percat is either Walkinshaw Andretti United or Tickford.
"Either of those teams have drivers, but some of them are off contract.
"Cameron Waters is one of those but is heavily expected to re-sign [with Tickford] and continue as is."
Tander played an important role in Percat’s rise to the main game, combining with the South Australian-born driver to win the 2011 Great Race.
The pair completed further enduro campaigns in 2012 and 2013, before Percat made his full-time debut in 2014 aboard a Walkinshaw-backed Commodore.
Percat departed the team after one season and moved to Lucas Dumbrell Motorsport, before joining BJR in 2017.
Tander and Percat completed three enduro campaigns together
Percat recently relocated to the Gold Coast, but Tander believes that will have no weighting on his 2022 plans.
"Two of the teams he's heavily connected to are Melbourne-based," Tander said of Victorian squads WAU and Tickford.
"Pretty much all the seats in Queensland [teams] are taken.
"If he’s going to drive for a Queensland team, the only ones left are Matt Stone Racing and I’m not sure that’s going to be the fit that Nick's looking for.
"He’s probably enjoying living on the beach, sunning himself and upping up his frequent flyer miles going to team pre-briefs and debriefs, flying backwards and forwards between Gold Coast and Melbourne."