Paragraph 23A F1
Where a person elects to be entitled to a lump sum under Schedule 5 or 5A to the 1992 Act or under Schedule 1 to the Graduated Retirement Benefit Regulations, or is treated as having made such an election, and a payment has been made pursuant to that election, an amount equal to—
(a)
except where sub-paragraph (b) applies, the amount of any payment or payments made on account of that lump sum;
(b)
the amount of that lump sum,
but only for so long as that person does not change that election in favour of an increase of pension or benefit.