Thank you for your warm welcome - it's always good to be introduced to a new community with such tolerance.
I've asked the question on two sites - since I am new to both forums, I have no idea which is the most active, or which has the most knowledgeable userbase.
In any case - anyone reading this thread, presumably, will either wish to know the answer to this question, or have the answer to this question and wish to impart their wisdom. Therefore, the thread adds value. There seems to be a third variety of potential viewer - the person who choses to add no value, but to snipe, instead.
We have a 1010S which may have the same interface.
We generally delete as we watch, so rarely need this, but a couple of months back I did want to do it for a selection of individual recordings and couldn't find any way.
For series there is a 'Delete whole series' (or similar) option in the menu somewhere I think, which I have used (once).
Delete series is an option when you click OK on a existing recording within a series folder with more than one recording within the folder. Despite it's name it doesn't delete the series reservation, it just empties the series folder. On odd occasions it stops part way through the deletions.