Firstly, there is NO mandatory LAPL groundschool requirement, even though the exams are the same.
Information Notice 2013/137
AMC1 FCL.115; FCL120 to Part-FCL confirms that the TK requirements (including syllabi) for the LAPL(A) and (H), including the 100 hours of instruction, are the same as for the PPL(A) and (H) respectively.
http://www.caa.co.uk/docs/33/sarg_IN_2013_137.pdf
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