OK, a breeder may need time to evaluate puppies but surely he/she knows how many orders he/she has (deposits taken shows a commitment to supply a puppy) and once the litter is whelped an email or a quick phone call "Yes the pups are here ! she whelped 17 and I have deposits on 16 of them so although I don't know which will be yours, there is definitely a pup for you !"
"I am so sorry. There was only one pup and we are keeping it. I will refund your deposit at once"
Even if the breeder is facing personal problems - obligations should not be ignored. An' if things are so bad there is no time for a quick phone call, I wonder who is looking after the babes ?
Its OK for you to show tolerance and patience but don't lose sight of the fact you have paid up-front and are entitled to news, positive or negative.
Good luck and may early 2019 bring you a Basenji puppy !