In a general sense inteviews in May would be reviewed by the DB in June. However, the precise "cutoff" date of when someone would meet a particular board is never known & there are folks due to circumstances who could find themselves slipping to the next DB due to a myriad of things. This doesn't happen too often but can & has happened. 4-6 weeks is the timeframe that is being told to interviewees on when they will hear something back from SWA.
Hope that helps,