http://www.ukvisas.gov.uk/en/howtoapply/infs/inf20transit#23021433 писал(а):Do I qualify for transit without visa (TWOV)?
If you are a visa national or a DATV national who is exempt, an Immigration Officer may exercise discretion and allow you pass through the UK on your way to another country outside the Common Travel Area (the UK, the Channel Islands, the Isle of Man and the Republic of Ireland collectively form a common travel area) without a visa providing that you:
arrive at a UK port on a ship and leave on the same ship within 24 hours
Так что, всё хорошо, пользуйтесь!