1. I agree with Med, we saw from previous he is on his way there
2. CAC is Cdn Armd Corps. X4 is reinforcement list. Probably in D Squadron of that Holding/Reinf unit
4. Think this is correct, not sure if it's any difference in purpose to a Holding/Reinf unit
5/6. Not perfectly clear but I think all Cdn Amd Corps X4 list. Just a move from D Sqn to E Sqn
7. G Sqn, presumably associated with the Elgins. D and E Sqns probably associated with several other Amd Regts each. Not sure if it's meaningful that he is posted rather than TOS (I suspect a clerical error)
8. 3 Cdn Armoured Reconnaissance (Recce) (GG Horse Guards)
9. G Sqn Amd Del Regt
10. CAC as above, E Sqn. I see Cas Section in the 'reporting unit' columns, so possibly wounded, possibly just sick. Usually see a specific indication if wounded
11. 3 Cdn Armoured Recce Regt (GG Horse Guards)
12. "SOS to". CAC as above, D Sqn. X3 is hospital list
13. TOS from X3 list E Sqn CAC
14. X4 (reinf) list 4 Bn. Each reinf unit in a forward area had multiple Battalions this is 4 Bn, he was in 5 Bn in 2.
15. Yes, same as 7.
16. Recce as in 8.
17. CAC as above. Note reporting unit is GGHG
18. Probably CMF as in earlier posts
A bit of a jumble but many entries are about movement within the reinforcement stream (X4 list) and a brief time in hospital (X3 list). Time with GGHG is with a combat unit. I don't find much value in the intricacies of the reinforcement process, it's all largely administrative, making sure they had sufficient reinforcments 'in the queue' for all of the units they were supporting. Doing largely the same tasks/training in each. If you were in the queue as a trained gunner for a unit, but another unit needed that trade, it all went out the window and you went where needed.
If you're keen to learn about how the replacement of men and equipment worked, I suggest 'An Army of Never-Ending Strength' by Arthur Gullachsen. It's focused on France etc. as far as I know, but the process was largely the same, just the unit names/numbers were different.