Reading the Regulation:
(a) Applicants for an LAPL(A) shall have completed at least 30 hours of flight instruction on aeroplanes or TMGs, including at least:
(1) 15 hours of dual flight instruction in the class in which the skill test will be taken;
(2) 6 hours of supervised solo flight time, including at least 3 hours of solo cross-country flight time with at least 1 cross-country flight of at least 150 km (80 NM), during which 1 full stop landing at an aerodrome different from the aerodrome of departure shall be made.
The credits are:
(c) Crediting. Applicants with prior experience as PIC may be credited towards the requirements of point (a).
The amount of credit shall be decided by the DTO or the ATO where the pilot undergoes the training course, on the basis of a pre-entry flight test, but shall in any case:
(1) not exceed the total flight time as PIC;
(2) not exceed 50 % of the hours required in point (a);
(3) not include the requirements of point (a)(2).
The total time as PIC = 6 hours
50% of the hours required in a) =10.5 hours
So it looks to me as the limiting factor is point (1) 6 hours
Let us assume that supervised solo is flight instruction, albeit not dual flight instruction. 30-21 = 9 hours!
No wonder they are having trouble with A levels!