For those with LOs that went from army crawling to classic crawling, how long did the progression take?

B

I know all babies are different but just hoping to get a rough idea.

My son turned 8 months today and over the last few days has got much better at army/commando crawling but has also started pushing up on his hands and knees and is also starting to rock.

If you’re LO did that too, how long was it before they could crawl on their hands and knees?