How long did your LO army crawl?

Brit • One and done so I'll be a FTM forever.
My daughter is 8.5months and just started army crawling a couple days ago. We're in the process of baby-proofing but it's taking a while. Just wondering how long your LO's army crawled for before crawling with their stomachs off the ground. Trying to guesstimate how long we have before she's going full speed.