My boyfriend is on probation for a felony and now they sent him a letter saying that his probation is being summarily revoked and has to appear for arraignment... what I'm wondering is if he'll go to jail or if they'll just restart his probation (because it's only they first time he's ever violated probation)??

If his probation is being revoked he will no longer be on probation and will be in jail. "Only the first time" is not acceptable to the Court.

He should consult with an Attorney.

If he has to appear for an arraignment that means there are some new charges he has to face.