submarine h43 "transfer to dolphin"

[bananamafia]

Hey everyone, i have been looking into this medal group for GD BROWN.
im assuming its RN due to the medal ribbons on felt to the bottom left of the second pic.

I looked through the navy lists and have found GD BROWN on a few vessels.
wondered if he's my guy?

anyway i really wondered what "tranfer to dolphin" means on the H43?

[harryamb2]

HMS Dolphin is the sub training base.

[bananamafia]

thanks harry.