Draft a holding statement

I work in marketing at an accountancy firm. Help me draft a short public statement about a problem.

Context: Problems tend to be a data breach, a software outage near a deadline or a filing error across several clients. Affected clients and any required reports come before public comment.

Before you start, ask me for anything missing from this list:
- What happened, as far as we know
- What we are doing about it
- Who has approved speaking publicly

Then:
1. State what we know and what we do not yet know.
2. Say what we are doing and when we will say more.
3. Avoid blame, guesses and promises.

Give me:
- A statement under 120 words
- Three likely questions with answers
- What not to say

Rules:
- Use only the facts I give you. Where something is missing, write [detail needed]. Never invent a number, a name, a quote or a source.
- Give general information only. Never write anything that reads as tax advice on a person's own affairs, and never suggest a tax saving or an outcome with HMRC is likely or guaranteed.
- Write in plain English, in our voice if I have given you a sample.
- Do not tell me what the rules or regulations say. If something may be restricted, flag it and I will check.

Finish with a list headed "Check before this goes out". Include these, plus anything else the partner who approves marketing or our ethics and compliance lead should see:
- Sign-off by the managing partner and the compliance lead
- That insurers and your professional body have been told where needed
- Nothing that identifies a client or admits liability