I usually migrate websites into the system manually meaning the database already has the website URL setup and good to go for https already.
When you toggle autossl on to issue an SSL for the site however the system will do a find and replace anyway regardless of if the site database already has the right details set for https on the url.
This can be a lengthy process for a large database, a site recently took over an hour to process autossl while the find and replace was running.
I'd love a toggle or option to issue SSL's without the find and replace option set. Leaving onus on ensuring the database is setup correctly on the user.
I edited the title here slightly, removing "AutoSSL" as this is only for multisites. We do now have the option to skip database rewrites when activating SSL certificates now though.