It has been a few years since we covered Google updating their site move recommendations document but they have. They basically now give different advice when moving a site based on if the site is a big/large site or small site.
The new document has a new section for small or medium sites versus large sites. It reads:
- Small or medium sites: We recommend moving all URLs on your site simultaneously instead of moving one section at a time. This helps users interact with the site better in its new form, and helps our algorithms detect the site move and update our index faster.
- Large sites: You can choose to move larger sites one section at a time. This can make it easier to monitor, detect, and fix problems faster.
It makes it sound like you can 100% move your large site all at once, but to monitor issues before they become major issues - Google does recommend you move chunks of the site instead of the whole large site at once.
This was spotted by Jammer on Twitter.
Forum discussion at Twitter.