I am not an accountant, however my understanding is that they...

I am not an accountant, however my understanding is that they are paying back some or all of the capital invested by shareholders/unitholders. Such an action usually requires the approval of shareholders/unitholders in a special/general meeting. As they are paying back our money, the taxation treatment of the money returned is different to that of a normal dividend/distribution. If your cost base is zero and they distribute 2 cents per BGP unit/share, then you will have made a capital profit of 2 cents per unit. This may be eligible for the 50% capital gains tax relief. I emphasise that I am not an accountant and everyone's personal circumstances will be different, so take advice if necessary.

I looked again at my payment advice from the recent distribution, and noted that on my statement the distribution is not classed as either unfranked or franked. There are however no franking credits listed so I assume it is an unfranked dividend, and my email from BGP tended to confirm this. I presume the company will provide further information in due course.

Like you I am pleased at this 'windfall', and am happy to receive it even if tax is payable.