Based on the past, when would the Dean’s List be announced for this past spring sem? And how? Would it be an email or letter home?
A letter home and sometime this summer I guess
It depends on your major. We never got anything from Mays. Here’s the qualification rules for those of you wondering 
http://student-rules.tamu.edu/rule11
I know Nuclear Engineering sent a certificate to your home - sorry can’t recall timing, but it didn’t take that long. Congrats on your achievement!
Aerospace Engineering also comes to the house.