If everytime collateral of coin change, all mns with old collateral will not stop to work. Masternodes once started ramain active even though the collateral for newer mns has increased. Hope this info helpful!
Thanks a lot. I was wrong with this. I always was thinking that it will stop to work. You made my day. I was searching details about this. Thanks so much ! I want to try mns even i am very new for this.