I usually have a feel under the seat for the end of the strap to find where to get the lifejacket at the appropriate time in the safety demo, but now I have become uncertain whether that will actually show me the presence of a life jacket. Is the enclosure under the seat designed so that if the life jacket is missing, the strap is not there (by attaching it to the life jacket, say)? Or is some more vigorous digging required to check if the bulk of a life jacket is present?