Help: Canadian WWII artillery terminology

[Crewman]

Hello,

The subject of this thread is the following document:

Royal Canadian Artillery, 2nd Canadian Corps, Counter Battery Policy, Operation "Totalize", Appendix L, Addendum A to RCA, Operation Instruction No. 5, 7 August 1944

I would like to ask you for explanation of several phrases or abbreviations related both to this document and generally to artillery operations.

The problems are the following. What does it mean?:

1. CB
The context is as follows: "CB programme", "CB bombardment", "CB task".

2. CBO
The context is as follows: "… ammunition at the rate of 30 rpg for 2 Cdn AGRA and 9 AGRA may be expended by the CBO" and "further ammunition can be made available to CBO on request" or "on call from CBO".

3. HAA
The context: "HAA Regiment"
Heavy Anti-Aircraft...?

4. HB
The context: "NIL – only for long range HB"

5. NIL
The context as above: "NIL – only for long range HB"

6. "Apple pie" bombardment
The context: "Apple pie" bombardment will probably be required on occasion during D plus 1 and D plus 2.

7. FMN
This abbreviation appears in the table "Ammunition allotment" and sometimes it is also "FMN/unit". The abbreviation appears in the first column of the table over the names of various units or sectors.

8. SP
This time I do not think that it is "Self-Propelled". The context is: "In sp of Attack". This phrase appears in the same "Ammunition allotment" table, this is a title of column No. 2 where the quantities of rounds are mentioned.
In spite of...? ... there would be something strange if so, but maybe I am wrong...?

9. RPG
Rounds Per Gun? The abbreviation appears many times in various contexts related to the quantities of rounds.



I will be very thankful for your consultation

Best regards

C.