Callum, a JSON-LD for SEO customer asked about changing the product urls and how that would impact Rich Snippets. I'll let him say it in his own words:
We're planning to do a big update of our product URLs later this month, as they're not written in a way that comes close to how a human would actually search for our products in Google.
What effect will changing our URLs have on the rich snippets in our search results?
Changing the urls might cause you to temporarily lose any Rich Snippets you have until Google re-indexes and reanalyzes the new urls.
This is because Google views a url as a single document. The same page at a new url becomes a different document to them.
That means Google has to index the new url, understand what it's about, figure out where it should be ranked across the entire internet, and then if it has structured data it will start the structured data analysis process.
One way to speed this up is to setup page redirects. This is a feature built-into Shopify and many other websites that will re-route visitors from one url to another.
Think of it as the Internet's version of a street detour.
There are temporary redirects which act like construction detours. e.g. use this other street for the next week while we tear up this road. These are called 302 redirects, after the HTTP code for them.
Then there are permanent redirects which act like new routes. e.g. we added an overpass here so you can go this other route. These are called 301 redirects and are what Shopify uses.
Changing product urls will hurt your traffic a bit but if you setup new permanent redirects using Shopify's URL redirects, you should be able to quickly recover.
If you don't have Rich Snippets for your store yet, why not?
JSON-LD for SEO is the easiest and safest option in the Shopify app store to automatically add the data Google requires.
It's already trusted by over two thousand stores and is among the top SEO apps overall.