While I don’t think the example given by stu675 is a good example it has to be said that the definition of a break couldn’t be much clearer.
“‘break’ means any period during which a driver may not carry out any driving or any other work and which is used exclusively for recuperation;”
Sorry but I don’t see what’s ambiguous about that, 
You don’t have to be able to leave the vehicle or freely dispose of your time, you just have to be able to use the time exclusively for recuperation.
I thought the first continuous 45min of poa can only be classed as a break when double manned? I had an infringement for Woking 6-9 hrs with only a 15min break but a couple of hours poa coz my tail lift hose burst.
It all depends on if the tacho software is set up right to only accept poa as break when a card is in slot 2.
How can there be 2 different POA’s depending whether your card was in slot 1 or 2?
Surely the card just records POA.
I was under the impression that all tacho heads assumed the first 45 of POA was counted as Break?
All will show driving times reset after 45 min of POA? That is the EU standard I believe.
Analysis software might be set up differently by different providers.
The tacho analysis software can be set up to read poa only if 2 cards were present when double manning for example. So at all others times when only 1 card is present it would ignore any poa as break. In tacho master it is simply a tick box for using double manning rules from memory.
Where has anyone suggested 2 different types of POA?
There is only one POA setting but how that is interpreted by analysis software can be very different, dependant on how it’s set up.
Ok, you’ve got the tacho head, the card and the software.
When the card is in the tacho on poa (or anything else) does the card record which slot it’s in? I would think not.
So how can software be setup to analyse poa dependant on which slot your card was in?
Yes the head does record on the card which slot it’s in.
Ok thanks 
" it is important to note that in the United Kingdom, PoA is not considered as a break. This is a different interpretation to much of Europe and as such digital tachographs view PoA as a break in their internal software. Therefore, if a driver was to take 45 minutes PoA in a digital vehicle, this would “wipe the slate clean” for the 4½ hours driving period being displayed to the driver. However, under the UK interpretation, this would not be the case and in those circumstances, if using PoA, the driver must be very careful to calculate their own 4½ hours driving periods and not to rely upon the display for compliance."
https://app.croneri.co.uk/feature-articles/periods-availability-explained?product=143
Yes. The first 45 are not counted as break in the UK, but UK tacho heads will show it as such, hence previous posts about problems when drivers were relying the head-unit to show them the correct breaks to take.
On a print out there are a few lines of dashes ---- going across the roll.
Various symbols are in the centre of the lines and details of the symbols are underneath each section.
If you only single-man the vehicle you will only see a ----1------
If you put your card in slot 2 you’ll see ----------2------------
And underneath that your activity when the card was in that slot. If you then start driving, there is a -----------1--------------
and your activities under that.
Page 14 fig 2