3. In relation to any person who arrived in England on or after 10th July but—
(a)before 9th August 2020, the principal Regulations apply as if the amendments made by regulation 2(2)(a) had not been made;
(b)before 4.00 a.m. on 11th August 2020, the principal Regulations apply as if the amendments made by regulation 2(2)(b) had not been made.