Explain a decision to people who weren't in the room

I need to explain a decision to people who weren't part of making it.

The decision: We're moving the customer database off the old system in January instead of doing the redesign everyone's been asking for. The old system fails about once a month now and each failure costs us a day.
Who I'm telling: the wider team, most of whom have been promised the redesign twice and will be annoyed
What we decided against: Doing the redesign first, which everyone wants but which would sit on top of a system we're about to replace. Doing both, which we don't have the people for.
What they'll object to: why the redesign keeps getting pushed and whether it's ever actually happening

Write it as one page they'll actually read.

Structure:
- The decision, in the first two sentences. Not the background, not the journey. The answer first.
- What it means for them specifically, in the next short paragraph. What changes on their Monday.
- Why, in four or five lines. The reasons that actually drove it, in the order that matters.
- What we didn't do and why. Say it plainly, because if I leave it out somebody will ask in public.
- What's genuinely a downside of this, named honestly. One or two lines. Don't sell it.
- What happens next, with dates or an honest "we don't know yet".

Then, separately: the strongest objection someone could make, and my honest answer. If the honest answer is weak, tell me that instead of dressing it up.

No corporate voice. Write it as if I'm saying it to the room.

What you get: A one-page note that leads with the decision, owns the trade-off, and answers the question you're dreading.