9. After paragraph (1) of regulation 10 of the Adjudication Regulations (setting aside decisions on certain grounds) there shall be inserted the following paragraph—
“(1A) In determining whether it is just to set aside a decision on the ground set out in paragraph (1)(b), the adjudicating authority shall determine whether the party making the application gave notice that he wished an oral hearing to be held, and if that party did not give such notice the adjudicating authority shall not set the decision aside unless it is satisfied that the interests of justice manifestly so require.”.