Crossword Help Forum
Forum Rules

Sorry, not 6 AC , but 5AC.

turast - pretty sensible approach, a couple of comments.

1. Don’t make assumptions about starting letters

2. Don’t worry about the word “different”, it just means that the encodings are different to each other.

3. One additional step - once you have the split of one and two letter encipherments and have done quite a bit of cold solving, you can see how certain encipherments interact with each other by looking at the down and across intersections. That helps give more information for your letter pattern last step

I've started on the process, and will eventually have a complete alphabet with an indication of whether they are single or doubl letter encodings. I've done this using two colours, red for single, green for double. There are other obvious ways in.
For example, 26 Dn is a three letter solution with 6 cells to fill.
When I'd filled in all the letters of my initial sweep (solutions with equal number of cells to letters), I could look at some of my cold solved clues, for instance 1 Ac & 1 Dn and see that (from number of cells against number of letters) both must contain only one letter which is a double encoder, and as it happens, 4 letters in each were already demarcated in my singles list, so I could safely conclude that the initial letter is a double letter encoder. I then went through all my cold solved in a similar fashion and identified letters which MUST be double encoders.
Two of the letters in 3Dn are definite singles, so the last one must be a double. Cell 3 & cell 5 MUST have the same encoded single letter. As must third cell in 1 across and first cell of 25 Dn. Amazingly,it's helping me enormously to write this all out

Yes turast, I’m about where you are. I’m not sure to start by making a huge assumption that S encodes to E. Also I don’t see why 9 across has so few possibilities. The four different double encodings could be taken from a whole list of them. Perhaps I’m missing something!

Whatever it is that you're missing unclued, I'm missing it too. I'm trying to figure the possibilities for 15d cross referenced to 4d and am getting nowhere fast.

Unclued - by looking at the down and across “clashes” one can see how the encipherments interact with each other.

Then one can work out that 9a has an slightly unusual letter pattern as you know certain letters are the same as each other even though you don’t know what they are.

That’s how I cracked it anyway, am sure one could also do it in other ways.

Thanks but this is too confusing for me and I shall wait for a few more nudges. Perhaps 4 down is the place to start?

Oh ok, sorry, was trying not to give too much away but clearly haven’t helped!

I have done much the same as Turast and identified (most of) the single letter substitutions. I have tried fitting single letter substitutions to answers with "helpful" letter patterns (e.g. 15 down) and using those elsewhere, which led to some plausible entries for a while before ending in a blind alley. As Gitto said earlier, this is more of a Bletchley Park exercise than a crossword, and I will also wait for more hints after in the week. I've 4-downing had enough of it for now.

I still have about 10 clues unsolved, but I have mapped all the letters bar Q (which I am assuming is in my unsolved 14a). I also have a cross-reference for most of them, but some of the single letters dont yet appear in a place where I can cross-reference.

The intersection of 22d and 24 and 30a suggests to me the O codes to a repeated letter - is that right?