From Wiltshire Council – updated news about Household Re-cycling Centres:

From Monday 8 June, you must book a slot before visiting a household recycling centre. Slots will be available to book from Thursday 4 June.

From Monday 8 June, all visitors to a Wiltshire household recycling centre (HRC) must pre-book a slot to visit beforehand. You can book a slot three days in advance, and slots will go live on Thursday 4 June. This is an advance-booking system, so you will be unable to book a same day visit to a HRC.

Up until the sites close on Sunday 7 June, we will still be operating a postcode entry system to visit HRCs.

The link is http://www.wiltshire.gov.uk/household-recycling-centres-booking-faqs