Flash loans have to be paid back in the same block or everything the flash loan funded reverts. And to ensure this happens, it usually is all wrapped up on the

Flash loans have to be paid back in the same block or everything the flash loan funded reverts. And to ensure this happens, it usually is all wrapped up on the same transaction bundle. But liquidations are only triggered on oracle updates. And those happen at fixed intervals (measured in time or price movement), and can only happen a block at a time, in blocks after the flash loan has been closed.