We will be taking the ferry from Salerno to Positano mid-July. I was on the website naplesbayferry.com website to look at schedules. It also allows us to reserve. Is it necessary to reserve, and if so how far ahead of time should I do so? Does a reservation provide an assigned seat? I've seen quite a few comments about the ferries being delayed or cancelled due to weather. Does this pertain more to the winter months or are weather delays common year-round? I appreciate any advice or suggestions!