Crawling?

My daughter Addison is 6 1/2 months. She is sitting up rather well and started to get up on her elbows and knees about a month ago. We figured she was getting ready to crawl. However, she is now using her arms to basically drag herself across the floor almost like an army crawl. We see her get up on hands and knees all the time and rock herself back and forth so we know she can do it. But she always lays back on her belly when she's ready to move across the floor (which is very quickly btw). Is this the first steps to regular crawling or could this possibly just be the way she crawls until she decides she is ready to walk? Any personal experiences would be appreciated. Thanks! 😊