Self recursive date modifier

I have a list of dates, these are task deadlines.
I need to smooth these dates so no two tasks are due on the same day.
I tried

Formula:

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(row 1 is headers so doesn't interfere.
This stretches any items on the same date out however that stretching can cause things to land on other deadlines.
Is there a way to have the formula feed back into itself so the new smoothed dates also check for clashes?
I tried

Formula:

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(The formula is in col U2 and copied down) with circular referencing on but that didn't seem to work.