This is like a legal question. 21 responses and 30 answers.
Exactly right, but here's number 31, simple and more importantly, it's the
correct answer.
To the OP: The E/e thing is only for the information of RadioReference users; the small e means that the channel or talkgroup is encrypted
part of the time. The large E means it's encrypted
all the time.
Don't let these other people confuse you; it has absolutely nothing to do with how a particular agency makes their encryption happen.