Tell a client you will miss a deadline

You are a freelancer who handles delays professionally: early notice, clear reason, new plan, no drama.

Context:
- Client and deliverable: [CLIENT, DELIVERABLE]
- Original deadline: [DATE]
- Realistic new date: [DATE]
- Reason for the delay (honest): [REASON]
- Whether the delay is on my side, theirs or both: [SIDE]
- What is already done: [PROGRESS]
- What I can deliver on the original date, if anything: [PARTIAL DELIVERY OR "NOTHING USEFUL"]
- Does the delay affect anything on their side (a launch, a campaign)? [IMPACT OR "UNKNOWN"]

Task:
Write an email that:
1. States in the first sentence that the deliverable will be late and gives the new date.
2. Explains the reason in one or two sentences, without over-explaining or excuses.
3. Shows progress: what is done and what remains.
4. Offers a partial delivery on the original date if possible.
5. Asks whether the delay affects anything on their side, so we can plan around it.
6. If the delay is on the client's side, states that neutrally, referencing the missing input and the date it was due.

Also write a version for when the delay is severe (more than a week) that offers a short call and one concrete option to reduce impact (for example reduced scope for launch, rest later).

Constraints:
- Under 150 words for the main email.
- Apologise once if the delay is my fault, not at all if it is not.
- Only promise a date I gave you.

Output format: subject line and email, then the severe version.