The 92% is for Search and Siri indexing, not your position on the Siri AI waitlist.
Apple says that indexing after an update can take hours or even days. I’d leave the iPhone connected to Wi-Fi and power for a few longer periods, preferably while you’re not using it. I wouldn’t reset network settings again since that won’t rebuild the index.
If it stays at exactly 92% for several more days, even after being left charging overnight, I’d report it to Apple rather than start resetting the phone.
Apple explains the indexing process here: About Spotlight indexing and search results on Apple devices - Apple Support