remove DOP = extend region why ?

Hi,

i have regions using speakerphone with DOP
i remove the speakerphone from DOP (0ms handles and extended treatment) so there’s 0 process in DOP. and suddenly the regions are extended like 3sec… why ?
and i can’t just grab all the regions and reduce them… looks like the extension is not equal so some region refuse to reduce in lenght… super annoying.