Don't know what you mean by Spanish holidays.?
Spain is a big country and each province will have different dates to the next one regarding school holidays, and some of those people from the various provinces will visit Benidorm according to their particular school/ employment rules.

The Costa Blanca government schools break up on the 20th June (infants and juniors) and on the 27th June (secondary schools.).....until the 11th & 17th September respectively.
Private schools may have different dates.

Sanjiiiiiiiiiiiiiii

You may be thinking of August when it is usual for the construction industry and factories to be closed both here and in other European countries. Although there is a move to try and keep things from shutting down in Spain, it is still a widespread practice and August is very busy everywhere.

Schools do break up on the 20th. June for 3 months, but for the last week of term the kids do little work, and this is when they go on their school trips.

Aqualandia is often on the agenda, so don't be surprised to see school parties there if you visit on the first few days of your holiday.

Thanks for all the advice appreciated

The Spanish Schoolkids are now on 1/2 days until they break up from school around the 18th June they go back mid september then they are on 1/2 days again til 1st October. Hope this helps. All August is when the Spanish take their holidays so very busy then.