Pigs may return from a show to the premises from which they departed for the show without triggering a movement standstill on those premises provided they are kept for 20 days after their arrival in a Defra approved isolation facility. Pigs must be isolated by themselves and not share isolation facilities with other species.
Pet pigs which are returned immediately to the holding they were moved from should be moved under a PRIMO walking licence issued by the Divisional Veterinary Manager (DVM).
Contact your local Animal Health Office, they should be able to advise you, but be aware that you should have applied for a Walking Licence before you moved them (Don't think you'll have a problem)
Good luck
Farmer