There are t&c's which have to be adhered otherwise should you have a warranty claim you may find hy refuse.
Read them then decide if the garage you intend to us can fulfil them.
i've found that by using the hy dealer although slightly dearer give peace of mind.
also,should you have a claim and use same dealer and have hy dealer stamps in book, i would expect them to fight your corner as a loyal customer.
however, the choice is yours to make once you have read the t&c's.