Only about 10% of the 8.5-tonne Tiangong-1 is likely to survive re-entry, meaning its descent poses only a small risk to people on the ground.
Experts have been trying to narrow down the time frame amid speculation over when the unmanned craft will crash.
The Aerospace Corp has predicted Tiangong-1 will re-enter the atmosphere seven hours either side of 2am on Easter Monday.
The European Space Agency estimated earlier that the craft will arrive after 12.25am on Monday, but the agency has stressed that the time is "highly variable".
The ESA's latest update on its blog states that they now predict the space station could land sometime between "the night of April 1 to the early morning of April 2".
The roughly eight-tonne Tiangong-1 will re-enter the atmosphere.
Leroy Chiao, a former NASA astronaut, said: "It's really hard to predict these things because many things influence the density of the atmosphere, and you know, how much grab it's going to have on the space craft as it comes down."
Jonathan McDowell, an astronomer at the Harvard-Smithsonian Centre for Astrophysics, tweeted this afternoon: "OK Tiangong-1 fans, now we're cooking.
"The @SpaceTrackOrg TIP window is down to + - 3 hours, during which time Tiangong-1 makes 4 orbits of the Earth.
Mr McDowell tweeted that Tiangong-1 is expected to land between 11pm to 5am UK time.
The space station is expected to land somewhere between 43 degrees north and 43 degrees south of the equator, a range covering most of the United States, China, Africa, southern Europe, Australia and South America.
But Mr McDowell's research has ruled out some of those locations. He tweeted: "Sad news for my followers in North America, India, Europe and Australia: if the current prediction is correct, Tiangong will not be falling on you."
Mr McDowell added in a separate post: "However, those of you in South America, Africa, the Middle East, Central Asia, China and New Guinea - or sailing the Pacific - should still pay attention."
Russia, Canada and northern Europe are all reported to be out of range.
Mr McDowell has also pointed out that if part of the space station lands in your garden "it's not yours, it's still China's".
Tiangong-1, which translates to "Heavenly Palace 1", was sent into orbit in 2011 for experiments as part of China's space programme.
The space station was set to have a controlled re-entry into the Earth's atmosphere, but the lab stopped working in March 2016.
Tiangong-1 had not been occupied for three years, so there is no way of knowing for certain where it will land.
Without being able to communicate with the space lab, controllers have no way of managing its descent.
China has predicted most of its debris will fall in the ocean as it breaks up on descent.