CAR 404.04 .....404.10 ....
(2) A Category 1 or 2 medical certificate is required for an air traffic controller licence.
(3) A Category 1 or 3 medical certificate is required for the following permits, licences and ratings:
(c) private pilot licence — aeroplane or helicopter;
So a Cat 1 is valid for an ATC license, and is valid for 24/12 months for that license.(6) Subject to subsection (9), the validity period of a medical certificate for a permit, licence or rating that is set out in column 1 of the table to this subsection is set out in column 2 if the holder of the permit, licence or rating is under 40 years of age and in column 3 if the holder of the permit, licence or rating is 40 years of age or older.
- Permit, licence or rating; Under 40 years of age; 40 years of age or older
1. Private pilot licence; 60 months; 24 months
11. Air traffic controller licence; 24 months; 12 months
A Cat 2 however is not valid for a PPL, but a Cat 1 is. Cat 3 or 1 for a PPL is valid for 60/24 months.
Nothing 'reverts', nothing changes.
Don't make up rules that are not written down. Keep things simple.