Publishing the same text everywhere is the whole point of fan-out — and the fastest way to make a pool of accounts read like a mail merge. The fix is not writing 270 captions by hand.
The reason to publish from one place is that writing the same post 270 times is absurd. But the thing that makes fan-out worth doing is also what makes it obvious: identical text, posted at the same minute, across accounts that are supposed to belong to different businesses.
Where identical copy actually hurts
Not everywhere. A public holiday notice, a price change, a product recall — these should be identical, and anything that varies them is a liability.
It hurts where the accounts have genuinely different audiences. A dental practice in one town and one in another do not share a catchment. An account whose followers read in French gets an English caption. An Instagram caption carrying a URL does nothing, because Instagram ignores links in captions, while the same caption on Facebook relies on it.
That last one is not a tone problem. It is a caption that does not work.
The three things worth varying
In practice almost all of the value is in three places:
- Language. If the account's audience reads in another language, nothing else you vary matters as much.
- The call to action. "Call us" needs the right number. "Visit us" needs the right address. A single shared CTA is wrong for every account but one.
- Platform fit. Links on Instagram, caption length on TikTok, what a Facebook Page audience expects versus an Instagram one.
Tone, house style and the things people spend longest arguing about come after those.
How this product handles it
Each account can carry its own voice rules — plain prose describing its tone, language, audience and the things to avoid. Written by the marketer, not structured into a schema, because the people writing them are marketers.
When a caption is rewritten for an account, those rules go into the prompt along with the original. You write once, review the variants, and publish. The original stays the source; the per-account text is a derivation you can see and edit before anything goes out.
The model doing the rewriting runs on the same infrastructure as the application rather than a third-party service, because an unpublished caption is brand copy and sending it off-machine should be a deliberate choice rather than a default.
Stagger the timing too
Identical copy is one tell. Identical timestamps are another, and this one also trips platform rate limits.
Publishing 270 posts in the same second is both conspicuous and a good way to collect errors. A few seconds of stagger between accounts costs nothing and removes the pattern.
What not to do
Do not vary a factual claim per account. A price, an opening time, a legal notice — if the rewrite changes those, the rewrite has introduced an error into 270 places at once.
Voice rules should say how an account speaks. They should never be in a position to change what it says is true.