I am doing LHR-ZRH-JMK with an overnight layover on 26 July so I am following this with interest as well, have read the Swiss website and it doesn't really make sense to be honest!


https://www.sem.admin.ch/sem/en/home...e%20exceptions


https://www.gov.uk/foreign-travel-ad...y-requirements

Uk Govt only says it has to be the same day transit.