Multiple projects in UGS stream invalidating eachothers PCBs

I have a question about UGS and how it is intended to be used with multiple projects.

Consider the following UGS depot in Perforce Helix:

//MyDepot/
├─ Engine/
│ ├─ …
├─ Projects/
│ ├─ ProjectA/
│ │ ├─ ProjectA.uproject
│ │ ├─ …
│ ├─ ProjectB/
│ │ ├─ ProjectB.uproject
│ │ ├─ …

I have generated PCBs for both projects and stored them in a separate stream. Now suppose I do the following:

  • Open ProjectB with UGS.
  • Submit a Code change to ProjectB

After performing these steps, the PCBs for both ProjectA and ProjectB are invalidated. This is not ideal since the PCBs for ProjectA should still be valid.

Does UGS have a way to avoid this or should separate projects generally be stored in separate streams?