Unable to update - Insufficient Space

I am trying to update the ARK Dev KIT.
It is currently installed on its own 120GB partition, a new installation from 2 weeks ago, no projects yet created so plenty of free space.
When I launch the Epic Games Launcher and choose “Update” it tells me "Insufficient storage available at “D:\ARKDevKit”. 63GB required. Available free space 49GB.

How big is this update? Is it going to do a full re-download, I would have thought the launcher should do a differential download?

Hello Maxximuss,

You will need the same amount of space as the initial download for the verification process. The team is aware of this, but unfortunately there is no work-around at this time.