Oh, well chosen, Steve! I loved this story. It goes into the stack of keepers. I say this as a person who is normally deeply biased against alt-history (with a few exceptions). True that the alt-history didn't play such a large part in this one so maybe my bias didn't take me far.
I loved the tone, the reader, the narrative voice, the plot, the setting, the language.
Pretty much everything. This totally hit my squids.
On a first listen I had to stop it and rewind, like many others have mentioned. I had too much going on externally and the story demanded concentration. However, on the second run, I was not bothered by accent, slang, or any other part of the writing or production. I didn't find the reader's accent to be too heavy at all.
Have I mentioned that I love this story?
Right, guess I have...