Recently, I had five weddings and my high school reunion on my calendar. With my busy life, I am a detailed scheduler, so I was extremely happy and relieved that I had the dates one year ahead because I could plan around them and not double-book or miss an important occasion.
How did I learn about these dates? It was from simple emails announcing the dates and locations for the weddings and reunion. Printed save-the-date cards will be mailed later. For now, I can reserve those dates on my calendar.
I highly recommend that you notify family and your best friends shortly after you know the date and location of your wedding. It's still important to send the save-the-date cards, but do it early, especially for summer weddings.
While wedding invitations are traditionally sent four to six weeks before the wedding, it's helpful to send them eight weeks (or more) prior to the nuptials, especially if you haven't sent save-the-date cards.