https://wccftech.com/spacex-churning-out-starship-prototypes-like-clockwork-the-fourth-iteration-is-now-being-built-from-the-salvaged-parts-of-the-previous-prototype/

SpaceX seems to be on a relentless roll lately, effectively deploying its honed logistics and engineering prowess to develop three Starship prototypes in around 60 days. Now, the space enterprise has started assembling its fourth prototype mere hours after the assembly lineup was cleared.

Remember when the third Starship prototype – known as the SN3 – was destroyed as a consequence of a poorly designed test coupled with an error on the part of the operator? Well, it seems that SpaceX is now leveraging that loss to expedite the production of SN4.