One thing to note about doing this, as I am having a problem with member services as I type. I transferred points into my March 2006 use year and banked them into my March 2007 use year. I now am trying to transfer additional points but am told I can't since I already did a transfer this year. I pointed out that the transfer was done during the March 2006 use year, but am told that since I banked the points into the March 2007 use year the system now sees transferred points in my March 2007 use year and will not allow me to do a transfer for this use year.
So apparently if you bank transferred points you use two years of transfer privileges.