The former champions moved up from last to seventh last year and have overhauled their car as they seek to build on their improvement.
"We have fixed a lot of the problem areas from last year but there's some new things we have to iron out. Part of the learning curve but it's going well so far," Albon told reporters during testing in Bahrain.
"It is tricky to put an absolute number on it. What's clear is it's going to take a while to get there," he added of the improvement.
"It's a totally different car to understand. I don't think we're going to hit the ground running but we can hit the ground jogging and have a good few races hopefully."
Williams had a difficult first day in Bahrain on Wednesday with Albon doing 40 laps and U.S. team mate Logan Sargeant only 21 due to a fuel pump failure and driveshaft problem respectively.
Thursday proved much more positive, with Sargeant covering 117 laps.
"We still had a couple of issues throughout the day," the American told F1 TV.
"Generally a positive day. We made good headway in the right direction. We know the direction we need to keep heading in. There's plenty of things we still need to fix."
The American said he was still fighting the car more than he would like.
"It's still a good car, we just need to iron out the details, get the balance in a slightly better place but we have plenty of ideas and tricks."
