What type of edit was it - can you provide a permalink?
Changing turn restrictions does not update the "last edited" data on segments. It's possible that, if that was the type of edit you made, it won't be "visible" to Waze.
We don't know the precise mechanics Waze use to determine their 90-days figure - or, indeed, if it's 90 days or 3 months. We just know that it's a process that seems to run fairly regularly, based on names disappearing from the AM layer.
Had enough of being ignored by HQ and insulted by Support. Taking a break for...