Hi, what I can see here is the colonization of the cells to form aggregated structures in some areas which led to some of the big gaps in between. I wouldn't consider them as enlarged cells. sometimes splitting them when they are close to 75% confluent helps.
Arinjay it is a commercial cell line! This occur only when at 100% confluence. Rupsa, I normally subculture them at 60-80% and I think they are enlarged cells, not empty gaps.