Perfin Help Please

I have these QE stamps that seem to have holes everywhere.. Is this a perfin or has the machine just gone west when cutting them :)



Heres another I cant quite make out.




Heres a couple more found hiding in the piles. Im guessing these are some kind of officials.. Please excuse me if posted in wrong place im still a newby :)

The Australian are OS for federal official use. Official Service? or Official Stamp? something like that.
The others appear to be, top to bottom
A E I
B & H
C O
anyones guess
I B (?)

No idea what these others mean, sorry.

If you hold them up to the light, you can probably read the initial easier. And look at them from the back as well. Sometimes they are perfed from the back, making them appear in reverse from the front.

The 4½d Wilding stamps have the A/EI (10/10,5) perfin of Associated Electrical industries Ltd of Birmingham & Sheffield (although from the postmark they presumably had works in Coventry as well).

It's interesting to see that some of these have the perfin the right up and some have inverted. This was quite common as often they were handpunched with two rows of stamps folded over to save time.

The ½d Wilding has the perfin B&H (11,12,10) which could be Buck & Hickman Ltd of Glasgow, Birmingham, Manchester & London, or Boosey & Hawkes Ltd of London W1, or British Band Instruments Co Ltd. I guess the last one was a Boosey & Hawkes subsidiary.

new keep asking and you will seek the knowledge you desire stamp perfins are for security initials to discourage theft.

Thank you all very much, again your assistance is very much appreciated,