My T encourages me to email her. I use it as a way to process sessions or deal with stressful situations or to just check in with T. There have been times when I'm struggling with something and T has specifically asked me to email her an update. However, my T does not give detailed replies to emails. She always replies, but it's usually just a sentence or two. Anything more detailed gets a phone call or waits until our next session. She also does not reply on weekends and usually only replies to emails in the morning during the week. So, she's asked me to always call for anything urgent.