The Bain/Steeply correspondence is a post-1993 addition.
This is material that was added after the early draft: absent from the 1993 manuscript, present in the published novel.
In the published book. Scene 128 (pp. 663–665); endnote-scene endnote-scene n269 (Marlon Bain letters)
Evidence. A single source reports this. On the added-post-1993 claim (Debraski's list; Moore's essay per our note names the surrounding items but not this one explicitly); the Dec-1994 witness confirms presence in MS-1994, consistent but not independent on the "added" claim. Documented by Paul Debraski's survey of the draft record; MS-1994 presence + proposed trim witnessed by Michael Pietsch's December 1994 second-read letter: "1094 Steeply/Bain letters. Cut way down. Keep letter 4 and concluding letter.".
Bears on. This difference bears on the following open questions: Avril's separatist involvements.
Further notes. Print keeps a multi-letter scene (scene 128, pp. 663–665) + n269 — whether/how far the "Cut way down" trim executed is UNVERIFIED.