I’ve heard that 24 hours is usually how long it takes for Fiverr to review a gig after you make updates to it, but it can take longer sometimes. If it takes longer, perhaps Fiverr has a review backlog. I’ve experienced delays myself, (including an actual glitch in the post-review process on a gig over the years), but my gig(s) have usually returned to their respective categories in due time.
There could be any number of reasons for a delay in your gig returning to its category. I encourage you to be patient and monitor the situation. If the delay is unnaturally long (and I’m referring to many days – not just 1-2 days), then maybe a simple inquiry with Customer Support is in order.
For the most part, though, your gig is usually just out for review. Let Fiverr do their thing, and keep watching for your gig to return to live status.