I wouldn't consider it particularly surprising that a big rewrite results in no new releases for a bit before the rewritten version is released.
There's clearly something wrong in their confidence about Rust Bun: If it isn't ready they should have said "whenever it's done", and if it is they'd have met some deadline by now. I suspect the speed was supposed to be part of the stunt, yet they seem to have encountered the 90:90 rule.