Peter Gammons dropped a bombshell on Twitter earlier today when he reported that representatives of Major League and NCAA Baseball have agreed to move the MLB Rule 4 Draft to July 1. With this change, the signing deadline for drafted players would also actually move up to July 15. Previously it had been one month after the end of the draft (that was July 17 in 2014) so now teams only have two weeks to come to an agreement with their amateur draftees.
The move to a later draft was one that NCAA Baseball had wanted for a long time, as the draft usually took place during the regional round of the College World Series tournament. This was obviously a major distraction for college coaches who wanted their players concentrating on winning the tournament and not on their professional careers.
Major League Baseball had less reason to make the change, although moving the draft back gives them more chances to look at amateur players before making a major commitment. The biggest gain for MLB is the shortening of the signing deadline. Major league teams hated protracted bonus negotiations that used to go on for as long as an entire year. Even the one month that it is now was considered excessive, since the bonus pools meant that teams usually had to make "take-it-or-leave-it" offers to their draftees with little room for negotiation.
However, there is a huge downside here for Minor League Baseball, and specifically the short-season leagues such as the Northwest League and the New York/Penn League. (This would be the Cubs' affiliate in Eugene.) Those leagues now start their season in mid-June and their rosters are often filled with newly-drafted college players. As it stands now, most teams would have trouble fielding a complete short-season team in late June. This would mean that those league would likely have to move their season back two weeks, which would cost them two huge weeks of summer revenue. Having the season end later would be fine as far as MLB is concerned, but it's not really an option for Minor League Baseball is concerned because attendance dries up after Labor Day and kids return to school.
Gammons did not report when this change would happen, but the earliest they could implement this would be 2016. If Gammons' reporting is accurate (and he's not often wrong) then it seems likely the 2016 draft would move back to July 1.
So the big winner here is NCAA Baseball and the loser is Minor League Baseball. For MLB baseball, it means more work and less time for them to work with players in their first professional season. That's a small loss, but since the signing deadline does not look likely to change, it's not likely to have a big impact on the top prospects who would often wait the full month before signing anyway. They would gain by being able to see players compete in the College World Series before having to make a decision on drafting them.