Overtime for part-timers
A. You are correct in that you are entitled to be treated no less favourably than a full-time worker in comparable employment — this is the law under the Part-time Workers (Less Favourable Treatment) Regulations 2000 (PTWR).
But there is a specific provision relating to overtime. Regulation 5(4) PTWR says that a part-time worker does not become entitled to overtime pay until they have worked the same number of hours as a comparable full-time worker. This means you must work over the 35 hours that your full-time colleagues work in order to become legally entitled to the time-and-a-half overtime rate.