Transferring between services

[lelapin]

I'm transferring from the Army Reserve to the Marine Corps (active component). I already filled out DD 368, talked to a recruiter and have had my decision okayed by my immediate chain of command, but what I wanted to ask you all about was something my squad leader said: that I have to write a memo to the CG about why I want to transfer.

What?

Have any of you ever done this/seen it done/heard about this memo/know if it's a DA or DD form? As always, any information is appreciated.