Time limits and notices waiving right to review
11. For the purpose of calculating the periods referred to in regulations 9(2), (3), (4) and (5) and 10(1), (3), (4) and (5), the notice is to be taken to have been given to the person in question—
(a)where the first class post is used, on the second working day after the date of posting;
(b)where the notice is delivered by hand, on the date of delivery;
(c)where electronic mail is used, on the date of sending,
unless the contrary is shown.