Force India may only introduce a B-spec car at the British Grand Prix, round nine of the season, revealed Sergio Perez.
Ever since the opening race of this season, which got underway with minimal pre-season running for Force India, the Silverstone team has been speaking about introducing a major upgrade.
Such is the magnitude of the changes but it would be a B-spec of the current VJM07.
There has been talk of the revised car debuting in Monaco, which was later pushed back to Austria. Now Perez says it may only run for the first time at July's British GP.
"We are obviously pushing very hard back at the factory, trying to bring the package together," he said.
"We would love to have the package for Barcelona, which didn't happen. I think Silverstone will be the first time we have a new package."
But despite that set-back, Perez feels his team has done an "amazing" job to even be sitting on 11 points from the opening four grands prix.
"I think the first four races have been better than expected.
"When you look at our position right now, we've done an amazing job, the whole team.
"We're only one point away from Lotus, 12 points from Red Bull. It's been a pretty good effort considering where the car is."
However, he fears this weekend's Spanish GP could be a trying one for the team but no more so than in previous races.
"I expect to have a difficult one, but on the other hand, not any more difficult than other weekends," he added.