Not new rules, 30 days visa exemption for UK citizens has been available for decades, best to get a tourist evisa before you leave or drop the 2 days. You'll need return/onward travel within 30 days to board your flight from the UK without a visa.
Put the visa number on the arrival card. Hand in the printed email with your passport. My entry stamp had Non Imm O hand written on it. No visa in the passport.