An interesting read that has a lot of face value for me, but I wonder if the "R" and "E" typings are stable through life, and how amenable are they are to chang

An interesting read that has a lot of face value for me, but I wonder if the "R" and "E" typings are stable through life, and how amenable are they are to change? The article comes across like "R" and "E" are set characteristics--almost like a personality trait. I'd really like to longitudinal see data on R/E mobility, and how fluidity between R/E types might be related to team cohesion overall.