Any building using the current partially built building counts, even if they change the height or shape. If the name changes it still counts.
I will add more years as they become relevant so feel free to bet on Other.
Jeddah Tower or Burj Jeddah (Arabic: برج جدة, pronounced [burdʒ dʒadːa]),[9] previously known as Kingdom Tower (Arabic: برج المملكة, romanized: Burj al-Mamlaka), is a skyscraper under-construction in Jeddah, Saudi Arabia. It is planned to be the first 1-kilometre-tall (3,281 ft) building and would be the world's tallest building or structure upon completion, standing 180 m (591 ft) taller than the Burj Khalifa.[10][11] Located in the north side of Jeddah, it is the centrepiece of the Jeddah Economic City project.
In September 2023, the Middle East Economic Digest (MEED) reported that Jeddah Economic City had restarted the project and a request for proposals had been issued for a contract to complete the construction of the tower. Fourteen construction contractors from the region, Europe, and China were given three months to prepare their bids.[88] In May 2024, the architect confirmed that construction would resume, and construction officially restarted in January 2025.[89] The Jeddah Tower is estimated to be completed sometime in 2028.
Although news articles are taking key phrases like "every 4 days" from the project's press director, we can measure progress against news articles.
https://www.argaam.com/en/article/articledetail/id/1874475
85 floors on 2026 Jan 21
https://interestingengineering.com/innovation/saudi-arabia-skyscraper-jeddah-tower
70 floors on 2025 Sep 11
It seems that although "construction started" in 2025 Jan and then Apr, it really started in Jul or Aug. The pace is now one floor every 8.8 days.
At this pace it will take close to 2 years to reach 157, though the floors will get smaller and hence faster. But then they have to add the big spire, finish the interiors and do a bunch of paperwork before opening.