The RSPCA welfare standards (set by the RSPCA’s farm animals department) are occasionally updated to take account of the latest scientific, veterinary and industry knowledge. You will be given three months' notice of any changes. A longer notice period will be given when changes are significant.
The RSPCA's new welfare standards come into effect:
Amends to RSPCA Welfare Standards for Laying Hens New RSPCA Welfare Standards for Farmed Atlantic Salmon