Hasn't that threshold been scrapped now?
EDIT: oh, apparently not, but it's now £39:
if you’re sent a gift with a value of £39 or less, which complies with the rules shown in section 2.4, it will be free from Customs Duty and Import VAT (gifts of alcohol and tobacco are subject to the limits shown in section 2.5 and gifts of perfumes and toilet waters are subject to the limits in section 2.6)