Maybe my family is just more economical than most, but as a child who hadn't seen his parents during the entirety of swab summer and frankly would have liked to see them, I still couldn't justify the expense to myself or to them to visit for eight hours. It's not to say that they won't be taken care of: every swab gets out on Mystic Flag Day (It's a rest day for the cadre too, remember!) but there are plenty of other long weekends and times during the academic years (even excluding Parents Day Weekend) when it is more convenient to visit and gets you more time with your child.
Also, speaking as a sailor for two years, there are plenty of times to meet with parents if they want to come up and visit, just usually after the season ends.
Call it a part of growing up, but dealing with the separation is something that has to happen: both for your swab and for you. I see my parents once a year now due to their having moved my second class year, and while it's hard, it's something we all have to do. I respect both of your rights to disagree but I will stand by my opinion on this issue. And it may be even more of an issue with some of the big changes that are coming to R-Day this year.
And to get to the crux of your question, as I suppose I should, Mystic Flag Ceremony is not listed on the Critical Dates Calendar for 2013-2014 and that dates hasn't yet been set.