Williams suffered a huge setback with the delay of its FW42 car - missing over two days of testing and missing out on valuable track-time and data collection.
Kubica completed 130 laps in the FW42 on Wednesday and he described his "mixed feelings" on the situation.
"Unfortunately we are running a bit late with our test programme because of last week's issue," Kubica said to RaceFans.net. "So it's a bit of mixed feelings because from one point it has been positive that we did a lot of laps.
"From the other side it is also true (there is) not a long time (until) we are going to race. We are not in the position we would like to be, especially from my side, from I think an engineering point-of-view also.
"We are doing a lot of gathering data stuff, checking different stuff but not really working on the car. I hope the next few days we will have a bit of time to start playing with the car and see how the car reacts to different things."
George Russell should take to the track on Thursday for another lengthy day of data gathering for the Hove-based team.