The Granta built to the new TC2 regulations has struggled for mileage in pre-season testing, and although the situation has improved in recent weeks, the British duo suspect they are facing a tough year.
"It is going to be a year of playing catch-up really, that's going to be the reality of it," double British Touring Car champion Thompson told AUTOSPORT.
"You can't expect to hit the ground running and be competitive against someone who has done six months of testing and development.
"This year is going to be another stepping stone to 2015.
"Everyone is miles behind Citroen anyway, so it is going to be Citroen, then Honda and then probably Chevy and us who have probably done similar mileage.
"At the moment it is logical to expect that if you're the last person to run the car, [last] is effectively where you are going to be starting from."
While Thompson has been part of the Lada WTCC programme since 2012, that season's WTCC champion Huff is about to begin his first season with the Russian team, having spent his title defence in a Munnich SEAT following the end of Chevrolet's factory effort.
"We are a long way behind where we want to be, but when these regulations and plans come around as late as they have done, it is very hard to get things ready," he told AUTOSPORT.
"A lot of restrictions and delays have not been through any fault of our own."
Thompson believes that rules breaks will allow Lada to make progress during the season, unless the team prefers to switch focus to the Granta's replacement.
"I hope by the middle of the season we will be on top it," he said.
"There are a lot of waivers and things and hopefully we'll get there with a development push on the car.
"We also have to build a new car for 2015, so how long do you concentrate on this car before you start thinking about the car for the following season?"
Follow the first races of the WTCC's new era as they happen with AUTOSPORT Race Centre Live's coverage from Marrakech, beginning 4pm UK time on Sunday April 13 - and watch video highlights on the AUTOSPORT WTCC page
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