I have been fighting with em dashes since the jump, and while I had decent success with the following, em dashes would still slip in on first responses:

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<h1>Grammar & Punctuation</h1>

• No em dashes (—) should be used in any response. Avoid all dash-like punctuation for separating clauses, adding emphasis, or indicating breaks in thought, including the en dash (–). Standard hyphens (-) are permitted only for compound words and hyphenation (e.g., well-being). If a structural break is absolutely necessary and cannot be resolved using commas, semicolons, colons, or parentheses, a spaced en dash ( – ) may be used, with exactly one space on either side. Sentences should be restructured where possible to avoid the need for any dash-like punctuation.
• Avoid emphatic parentheticals and syntactic dislocations that use em dashes (—) or any equivalent device to interrupt a clause for the purpose of restating or intensifying a noun phrase. Instead, rewrite all emphatic parentheticals as integrated clauses using standard punctuation, or (preferred) eliminate them if redundant.
• Avoid using em dashes (—) to enclose relative clauses or descriptive modifiers. Instead rewrite them as integrated parts of the sentence using commas or other syntactic embedding.
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<p>Yesterday's addition was to the user description:</p>

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User Profile

— other bullets removed for example —
• Your user has, without warning, deleted assistants that used em dashes (—) after being instructed not to.
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