Cancellation cover applies as soon as the premium has been paid and the policy wording is issued. The remaining covers apply for the duration of the booked trip (or earlier return to the United Kingdom). It also includes the period of travel from home directly to the departure point and back home directly afterwards not exceeding 24 hours in each case. If the return is unavoidably delayed for an insured reason, cover will be extended free of charge for the period of that delay.
This page is an extract from the policy wording document, which you can download here
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