As we reported, Jamie is now under criminal investigation for allegedly breaking a door down and putting his hands on Sean. A temporary restraining order is now in place prohibiting Jamie from having contact with Jayden and Sean.

Certain members of Britney's team believe Kevin might go to the judge overseeing the conservatorship and ask to remove Jamie because he's ultimately responsible for the welfare of the children -- since he oversees their mom -- children with whom he's temporarily prohibited from having any contact.

Our Britney sources believe Jamie is secure in his role for one reason ... there's really no one else who can handle it. The judges associated with the conservatorship over the years have acknowledged Jamie righted the ship when Britney was at her worst -- in danger of losing custody, bleeding money and extremely unstable. Britney is now flush with cash, has joint custody and by all rights is considered a good parent.

As one Britney source put it ... "Jamie certainly has his flaws, but everyone knows he's done a good job and there's no one else who can do it."

The wild card -- will Britney's mom, Lynne Spears, make a move to wrestle the conservatorship away from Jamie? As we reported, Lynne expressed an interest to become involved in the conservatorship earlier this year, after a social media campaign went after Jamie. She spent time with Britney in L.A., reconnecting after years of estrangement, but she's been in the background ever since.