39C. Supplies spanning specified change: tax chargeable at new rate and old rate without election

Where a supply spans a specified change that is an increase in the tax rate or that results in the supply becoming a standard-rated supply and, before the date of the specified change —

the invoice is issued for the supply; and

either of the following applies:

the consideration for the supply is not received or only received in part;

the supply is not performed or only performed in part,then —

tax is chargeable at the new rate —

on the lower of —

the value of the supply for which any consideration is received on or after the date of the specified change; and

the value of the supply performed on or after that date; or

if the value in sub-paragraph (i)(A) is the same as the value in sub-paragraph (i)(B) — on that value; and

tax is chargeable at the old rate or (if, before the specified change, the supply is a supply that is not chargeable to tax) tax is not chargeable on the value of the supply less the value on which tax is charged at the new rate under paragraph (c).