Yes. Different dockets, different dates and potentially different batch numbers.
Yes, that would be more or less it.
Yes if you want to go to the bother of entering every single docket / purchase. Dont get too worried about it. Once you have a few in you will be fine.. just dont show a docket for one you havent entered
Just go to the place you buy your ration and ask for an account statement for the last 6 months if a new entrant in to BB. They should be able to print out all purchases in a couple of sheets. No need to write into farm book.