When did the Great Collapse happen in Divinity's Reach?

Hey all! Quick lore question. Does anyone know when the Great Collapse in Divinity's Reach happened? Like, when the actual event where the arts district fell into a sinkhole occurred? All I could find is that it was "sometime before the main storyline," but not how long before (weeks? months? years?) and I was wondering if there was a consensus on this.

Thanks in advance!

There is no specific timeframe given but it would have been weeks or months at most, given that it was treated as recent - same with Thaumanova Reactor's explosion - and many of the people who lived there were waiting outside the fences until the Crown Pavilion was created halfway through Season 1.