User blog comment:Ryuzakiforever/When Will FUNimation Catch Up?/@comment-4374114-20150203150627/@comment-38.112.107.82-20150203161646

The sizes and release times are based on how big the season is. The size may be 11 or it may be 13, based on how big the season is. If they did every set as 13, then they would end up with one set at the end of the season that was only 6 or 7 episodes, and that would piss people off.

As for timing, they can crank a full set out in a month and a half or so, but once they hit the end of the season, they let it spread out instead of leaving a six month gap while they negotiate for the next season. (Which is why we're waiting an extra two months right now for a dozen episodes that are probably basically done already.)

Regardless, their average rate seems to be about one season a year, so you should be checking the episode numbers that they'll be getting rights for. Then, if you want numbers per disc set, divide it as evenly as you can into sets between 11 and 13. And if you want release dates, start in september, and spread it out as evenly as you can over a one year period.