When running two concurrent pipeline builds, the second one will contain the changes from the first (so long as the first hasn't finished running when the second pipeline starts).
CL 1 starts a build
CL 2 starts a build
Then Build #2 will contain CL 1 and CL 2 even though it is really only "newly" building CL 2.
This causes issues for reporting (e-mails, jenkins ui, ect) since it makes it look like CL 1 was first introduced in Build #2 when it was really introduced in Build #1.