She's just not working on large motor right now, it sounds like. She's "keeping her hand in" by still cruising, so she hasn't totally dropped large motor, but she's not focused on it. I'll betcha though she IS intent on something else. Verbalizing or Pincer (fine motor)? Cause & Effect or Object Permanence -peekaboo is a great example- or Grouping (cognitive)? Sensory Integration (tastes, smells, textures/feels, sights, sounds)? Emotional? Growth Spurt? (growth spurts throw everything out of wack, because they're so focused on getting enough calories and figuring out how their bodies work "bigger" than they were before, and sleeping)
No baby "does" everything in the same order... although there's often "base" reasoning that makes sense. For example; Fast Growers tend to be late rollers, sitters, walkers... but early in cognitive, emotional, &/or fine motor... because they can't keep on top of the muscle changes with their growing bodies for large motor, but CAN keep up on developmental milestones that aren't affected by their fast growth. Bilingual children have MUCH SLOWER verbalization (but not late, the milestone actually changes when there are 2 or more languages because parts of the brain do not atrophy like they do in mono language speaker).
The human brain is just incapable of moving through development in a straight line. There is just TOO MUCH to do. So the brain picks and chooses certain areas to work on. Then once a certain proficiency is reached, they "drop" those areas (regressing is common as well) and move on to something else. Then they come back to the dropped area, drop it again, go somewhere else. Children's development goes by leaps and bounds, because they get INTENT on certain areas, and then backtrack or move laterally to develop other areas. It's why "normal" has MONTHS long ranges, and sometimes over a year or two in the 'normal' range.
For my own son, I actually forget. One of my earlier posts probably has the actual age. I know he was well over a year old. Technically he learned at something around a year and a few months old, but wasn't impressed, and kept speed crawling for about 6mo after he learned. (He was all about speediness). Then, of course, he started walking/ running/ hopping/ skipping/ sommersaulting/ etc. all in the same WEEK, so he was 'caught up' to other kids who had been learning those skills gradually over 6 months that he'd been speed crawling.