Bilia to Francesco II Sforza, 22 November 1527

TASK: take a partial decipherment further: Bilia to Francesco II Sforza, 22 November 1527
This page: https://dbourdeau.github.io/cyphersolver/further/bilia1527.html

You are helping a public research project finish reading historical cipher letters. This one is read in part:
the key works, but some pieces are still open. Your job is to close one or more of the open gaps below.

THE READING
  Write-up:   https://dbourdeau.github.io/cyphersolver/bilia1527.html (read it first: how the text was read, the key, the reading)
  Date:       1527
  Outcome:    known key applied · partial
  Read now:   80.9% of the deciphered cipher tokens give sense (pieces below may be untouched)
  Files:      https://github.com/dbourdeau/cyphersolver/tree/main/targets/bilia1527 (NOTES.md, key, transcription, reading, scripts)

OPEN GAPS (from NOTES.md, "## Remaining gaps")
  1. [no-key-material: needs a new source] f. 102v, seven cipher lines (118 signs): words but no sentences - blocker: no-key-material; checked on view 165 at full size and decoded with R5258 (23 Oct 2026, b24); R.29, 8?, the open rectangle and o.19 have no value on the key sheet, £, φ, mp only context values
  2. [needs-physical-access: needs a new source] f. 102v line ends at the gutter (one or two signs a line) - blocker: needs-physical-access; only the BnF microfilm scan is online, the last signs curve into the binding
  3. [no-key-material: needs a new source] name code B.58 (f. 102r line 2, the old man Bilia dined with) - blocker: no-key-material; not on the R5258 nomenclator (checked on the sheet image); one occurrence
  4. [not-attempted: doable now] about 28 doubtful signs on f. 102r (8 image-check splits, "Theophimo", "pervitio", "papre", "tompi", "vechilza", £ as l or et, B.3?) - blocker: not-attempted; AI-only transcription, a human reading of view 164 at full size would settle most

ALREADY TRIED (from NOTES.md, "## Escalation")
  [x] siblings: no. 42 (same date, to the ambassador Taverna) opened on view 159: a different cipher, not this key; no decipherment or clear copy of no. 43 in fr. 3013 (contributor's search, and views 159-167 looked at here)
  [x] clear-pages: f. 102v clear text is the close, date, a postscript about the Emperor going to Valencia for Christmas, and the signature, not a decipherment
  [x] known-keys: R5258 (Bilia's key) applied; R5237 ("Cum Egr[egi]o Bilia", numeric alphabet) does not fit (contributor); R5256 is a different syllable table
  [x] print: CSP Spain iii/2, CSP Venice iv, L&P iv, Cryptiana searched by the contributor: nothing. Not checked by them or here: Cerioni 1970 (the Sforza key edition) and Giudici 2018
  [x] key-rebuild: five sheet-less signs given values from context by the contributor; x and θ values confirmed here on the R5258 sheet image; B.58 not on the sheet
  [x] retry: f. 102r and f. 102v decoded again here with our key; 23 Oct 2026 f. 102v checked on the full-size view 165 (b24): stays decoded, not read

STEPS
0. Set up. If you can run a shell, fork and clone the repository and work inside it:
     git clone https://github.com/dbourdeau/cyphersolver.git
   Then read, in this order: CONTRIBUTING.md (how a contribution is sent and credited); README.md, sections
   "Repository layout" and "Conventions" (how readings are measured and named); targets/bilia1527/NOTES.md in full, and the
   key, transcription and reading files it names; lang/README.md (shared language models).
   Work in targets/bilia1527/. Add your findings to NOTES.md under a dated heading without rewriting what is there, and
   update the "## Remaining gaps" line of every gap you close. Keep WORKLOG.md there: one dated line per step
   (hypothesis, value tried, solver run, crib, control), failures included. Do not edit docs/ (the site is generated).
   If you cannot run a shell, fetch the files from the links above and keep your work in files you send with the issue.
1. Pick a gap. Start with the ones marked "doable now" (open-codes, not-attempted, left-open): the images and the key
   are online, so they need only work. A gap marked "needs a new source" (no-key-material, too-short, illegible,
   needs-physical-access) can be closed only by something new: a key
   or a deciphered sibling found elsewhere, a better image, a printed edition or calendar, a photograph from the archive.
   For those, search for that material first, and say where you looked even when you find nothing.
2. Start from the existing key and transcription in the folder. Do not rebuild the key from scratch, and do not
   re-read parts that are already read unless you find an error in them.
3. For a code group or sign value: list every place the group occurs, show how each reads with the value you propose,
   and say what still does not fit. For a passage: re-read it at the image and give the folio and line. For a missing
   letter or leaf: say where it is held and how it can be reached.
4. Measure again. Apply the key to the whole text, write the reading file, and count the share of cipher tokens that
   give sense (not an estimate). The reading is "complete" only when (1) at least 95% of its cipher tokens give sense;
   (2) no gap is left untried; (3) every letter in it is covered; (4) what stays open is scattered code groups or names,
   or pieces blocked from outside. Otherwise it stays "partial": say which gaps are still open and why.
5. Be honest. Mark every uncertain word with [?], leave unread groups as their numbers or signs, and never fill a gap
   with a plausible guess. A gap retried and still open, with what was ruled out, is worth reporting.

REPORT BACK
With a clone: open a pull request with your changes to targets/bilia1527/. Say in the description which gaps you worked on,
  the share read before and after, and how you want to be credited (name, initials or handle, and a link).
Without one: open an issue: https://github.com/dbourdeau/cyphersolver/issues/new?template=further-reading.yml&title=Further+reading%3A+bilia1527&page=bilia1527.html
  Give the write-up, the gap you worked on (its line in Remaining gaps, or the code group, folio and line), what you
  propose, the evidence (every occurrence, the images or sources), the share read before and after, your step log,
  and the tools and AI model you used.
If you cannot open issues or pull requests, write this report for your human to send. Credit goes to the person who sends it.