“(2) Where this section applies in relation to a provision of regulations, any person who fails to make a return in accordance with the provision shall be liable— ( a ) to a penalty or penalties of the relevant monthly amount for each month (or part of a month) during which the failure continues, but excluding any month after the twelfth or for which a penalty under this paragraph has already been imposed.... ... (3) For the purposes of subsection (2)( a ) above, the relevant monthly amount in the case of a failure to make a return— ( a ) where the number of persons in respect of whom particulars should be included in the return is fifty or less, is£100 ”
“For the purposes of this Act..... where a person had a reasonable excuse for not doing anything required to be done he shall be deemed not to have failed to do it unless the excuse ceased and, after the excuse ceased, he shall be deemed not to have failed to do it if he did it without unreasonable delay after the excuse had ceased”