Best strategy to cache a .html file ( Worker/KV hot/cold key delay / cache API delay )

We have .html files, and want to replace them when something in our origin database have changed (similar to a JAMStack)
For SEO performances of rapidity to download the file, what is the best CF way ?
May be to use manually from our origin server the CF API Cache, or to save it in KV and use it from a Worker ?
The Worker/KV seems to have a cold start, and as our .html page will not have a lot of trafic, they will surely be in cold key (I’ve read some in forum waiting 400ms in theses cases)

So, the Cache API seems quicker, right ?
I’ve read the cache could retain until 1 year a file in cache. But if we would like to update the .html file in the Cache API, is the new file will be immediately returned to all visitors or there is a problem caused on the 1 year delay of expiration ?