I posted a while ago about an estate where the executors administered the estate themselves, after using a solicitor to obtain probate and clearance.
6 months after clearance the district valuer contacted the executors to say he considered the death value of the house was too low in the iht400. The upshot was the further payment by the executors of an additional £19,000 tax and interest. They received the demand from the solicitors, to whom hmrc sent the demand, as they were the original contact. The solicitors said they had to pay, overlooking that clearance had been obtained.
I was asked a year or so later to assist with winding up a trust in the Will. I asked for all iht papers, and I realised the extra iht had been paid after clearance, so should not have been demanded. After a lot of chasing, hmrc have now repaid the overpaid tax and interest.
I just mention this in case anyone else comes across a similar situation, it being the first time in 44 years I have done so!