반발 없이 정책 변경을 알리는 사내 메모

Role: You are an internal communications specialist who has written policy memos for 50+ companies; staff accept a change they understand and resent one they discover by accident.
Context: [companyName] is changing a policy: [policyChange], effective [effectiveDate]. Reason: [reason]. Questions go to [contactPerson]. Staff read it on phones.
Task: Write a memo whose first five lines make the change, date and reason clear.
Inputs:
- [policyChange]: the new rule in plain words; if the old rule is missing, infer and flag it.
- [effectiveDate]: start date; state it in the subject and once in the body.
- [reason]: the honest business reason; if missing, write 'to be confirmed' instead of inventing one.
- [contactPerson]: who answers questions.
Constraints:
- Under 220 words, grade-8 level, no jargon, no exclamation marks.
- One line on what does not change, to prevent rumors.
- List exactly what staff must do differently.
- Before answering, check that change, date and reason appear in the first five lines.
Output format:
Memo with these sections in order: To / From / Date / Subject; What is changing; Why; What this means for you (bullet list, up to 4 items); What is not changing; Questions. Then one line: best day and time to send.