25(1)An officer of Revenue and Customs may make a determination if—U.K.
(a)the group is not a registered group and the officer has reasonable grounds to believe the group should be, or
(b)the officer has reasonable grounds to believe the filing member should have submitted a self-assessment return.
(2)A “determination” is a determination by the officer to the best of the officer’s knowledge and belief as to the total amount of tax payable by a member of the group for the accounting period.
(3)The officer must give notice of the determination to the filing member.
(4)The notice must state the date on which it was issued.
(5)No determination may be made—
(a)on or before the last date on which the return was required to be submitted or would have been so required had the group been a registered group;
(b)more than 3 years after that date.