Leads in different partitions

[Anonymous]

We have 2 partitions in our instance - US and UK.  UK sent out emails last week using an imported list.  After sending it out, somehow, some leads showed they were removed from US nurture tracks.  Does that mean it was included in the US nurture track and then was removed somehow?  They shouldn't even get into US partition at the first place.  How can I confirm leads in one partition won't get mixed up with another partition?

Thanks!
 

[Anonymous]

If I set up the way like below, would that work and separate two lead partitions?

[Josh_Hill13]

Depends on the Default's lead partition flow. Perhaps those UK imported leads were dupes of a US lead and they were moved?