1.C.S.B.D. (4 R.H.U.) (C.R.#1) What and where?

[Glen]

I'm chuffed by the prompt responses on this forum, so I'm going to go ahead and fire off some more questions!

After 2 CACRU, my grandfather was sent to Philippeville (now Skikda), Algeria. I'd like to know exactly where he was in or near Philippville.
Here's what I transcribed from his war logbook thingy:

S.O.S. 2 CACRU to 1.C.S.B.D. (4 R.H.U.) (C.R.#1) w.e.f. 10 May, 43

I think it translates as:
"Struck off Strength 2 Canadian Army Corps Reinforcement Unit to 1 Canadian Special Base Depot (#4 Reinforcement Holding Unit) Canadian Regiment?? #1 with effect May 10, 1943"

Does anyone know exactly where 1.C.S.B.D. (4 R.H.U.) (C.R.#1) would have been?
Does anyone know what the C.R.#1 stands for?

Here's what I have found so far: Charles Comfort's book "Artist at War" makes reference to a place "south from the port in Philippeville down a tortuous road...then came the Cork Forest and the tent line of No.1 Canadian Base Reinforcement Depot, British North African Force"
I remember hearing in an interview with my grandfather talk of "the cork forest" as if it were a specific landmark. The problem is, it seems there are as many cork trees in Algeria as there were olive groves in the Italian Campaign!

Any help is much appreciated!

Glen.