http://www.bbc.co.uk/news/uk-45262708
ASA say that 'summer holidays' only applies to June, July & August, so to advertise for summer holidays that can only be taken in September and October is misleading.
Only if you have children at school, surely? And even then, June is not 'summer holiday'.
Before we had school-age dc, we always took our summer holidays outside peak season. Even in England we had lovely summery weather right up to October half-term.