Having cancelled a planned shakedown, Williams now announces that its pre-season testing programme is delayed until Tuesday.
In a brief statement issued this morning, exactly 24 hours before testing is due to begin, Claire Williams said: "Unfortunately, we have had to delay the start of our pre-season Barcelona test to Tuesday morning. We have had an incredibly busy winter at Grove getting the FW42 prepared for the season ahead and, despite everyone's best efforts, we need some more time before it will be ready to run.
"Our absolute priority is to always ensure we bring a car to the track that is the best that it can be," she continued, "and sometimes that takes longer than you'd anticipate or like. It's clearly not ideal, but equally it's not the end of the world.
"We will obviously have our work cut out to recover the time lost but we still have seven days of testing left and we will be maximising that time to prepare the car for the first race."
The team has yet to reveal its 2019 contender in the flesh, the car presented at the livery launch earlier in the week being it's ill-fated predecessor.
On Friday, amidst speculation that the Grove outfit was facing a race against time to be ready for the start of testing on Monday, the team issued a number of renderings of the new car.
Robert Kubica was due to drive the FW42 on Monday morning, handing over to teammate George Russell for the afternoon. However, the revised schedule sees Russell drive the car on Tuesday morning before handing over to Nicholas Latifi. The Canadian will be back in the car on Wednesday morning before handing over to Kubica in the afternoon.
The Pole drives on Thursday morning before Russell brings things to a close in the afternoon.
The team has announced that there will be no media sessions on Monday.