It depends on the moment when you subscribe. These are the different possibilities:

You subscribe for the first time in your home country and before your trip:

No waiting period applies, you would be covered from the first day !

You renew your contract and there is not a gap in cover:

No waiting period applies so you would be covered from the first day !

You subscribe for the first time when you are already abroad:

Did you forget to subscribe an insurance before travelling? You can subscribe if you are already abroad, but in this case a 12-day waiting period applies.

You renew your contract when you are abroad and there is any gap in cover: 

We send you two emails before the end of contract for you to not forget to renew. Anyway, if you forget and there is a gap between the end of one contract and the beginning of the new one, a 12-day waiting period applies.