I understand that the block times are based on averages over the year and therefore sometimes the flight time will be longer than the block time but I don't see how it can be possibly legal to design a pairing knowing that at some times of the year it will exceed the flight time limitations. If that is the case it should be rostered with heavy crew (or longer layovers or whatever) during the times of year it is likely to be illegal. If there is no way you can complete the flight without discretion then surely an ASR is required. Moaning about it on here won't get anything changed.