Almost right. The app notifies your nominated contact, not Coastguard. It is up to the nominated contact - your partner say - to take action by notifying Coastguard etc. There is no way that Coastguard could check on all the overdue calls which are not self cleared on the East Coast, they only check on West Coast Bar crossings. After all, on a typical summers day like yesterday, the Coastguard ops centre will take well over 1000 calls.