If you have an overdrawn loan account with your company, there is a tax charge on the company unless the loan is cleared within 9 months of the end of the period to which accounts are prepared.
Nasty anti-avoidance measures have been introduced to stop companies avoiding the tax charge. In particular when the loan is at least £15,000 and is repaid just before the 9 month deadline but with the intention of re-borrowing from the company, and that intention is carried out, the amount repaid is ignored. That results in a tax charge arising as if the loan had not been repaid in time.
This is likely to catch common arrangements where all withdrawals from the company are treated as debits to the director’s loan account and are then cleared before the 9 month limit by way of voting a dividend or salary.