I am working on a project with a partner company (X) for another client (Y). The team at X works with us on some aspects of the project and is the primary interface with the client Y. So, in a way, the partner company X is our intermediate client.
The team at X has raised unnecessary concerns about the project being not on schedule on several occasions. One day they say everything is fine and great, and a few days later I get a call asking why this work is not yet done. I spend significant amount of time on phone calls and emails convincing them that the project is in fact on schedule.
They even ask about tasks which were not in the plan. I keep a good trail of emails and documents, so I can usually make it clear that these tasks were not agreed upon. However, this has started to get annoying, as I end up spending my personal time resolving these nonexistent concerns.
Forwarding old emails, pulling out the project plans and progress time adds up to a lot of unproductive time. Is it right for me to indicate that I would bill all this unproductive time?
My concern is they may, in turn, charge Y for this time, and I just think it is unfair to Y.
This question is not a duplicate of the suggested question (Are constant changes to a projects requirements a sufficient reason for terminating a contract?) because I am not looking to terminate the project, just to send a strong message that solving these imaginary problems is highly unproductive and costing us financially and morally.