The gov.uk website recommends having the vaccination in autumn/ early winter before the flu season kicks in.
It should be reasonably effective for up to 6 months, so if you have it in September, it ought to be ok until March.
Personally, I book mine as soon as they are available. If you wait, they often run out.
Rupert Lowe and the “rowers” haha
Our seas and beaches and climate change



