Claim for overpaid tax after contract rescinded

The taxpayers entered a contract to buy a house. They paid a deposit to the vendors with a view to completion several months later. They completed a stamp duty land tax return and paid the tax due. However before completion they decided to abandon the purchase and the contract was rescinded. They submitted an amended return and asked for a repayment of the tax (FA 2003 s 44(9)). 

HMRC said the claim was out of time because it was 14 months after the original form had been submitted. The officer invited them to claim under Sch 10 para 34 but said it would be challenged. This all happened and the taxpayers appealed.

The First-tier Tribunal agreed with HMRC that the s 44(9) claim was out of time. To be valid it would have to be made within 12 months of the filing date of the return. 

However Sch...