This question appears to have never been answered. And I'm now having a similar issue. Have built several dozen PROJECTS for my homebuilder client. And up until now, for the past month, the job PLs have been working and accurate. Tonight I log in to his books and the labor costs are GONE from his project PLs. If I review the TIME ACTIVITY reports in the projects all of the times are detailed there. But they no longer populate into the PLs. No explanation as to why.

As an aside to this, this is the 3rd issue I've had with using this feature of QBO (client on Advanced version). Projects feature is buggy and unstable. Suggest anyone considering using it tread lightly.