Give people room to report uncertainty before it becomes a hidden delay.

Uncertainty does not disappear when it goes unreported; it just gets expensive. If admitting that you are not sure costs someone standing, they will hold the doubt and hope it resolves, and it surfaces later as a missed date nobody could plan around. What people tell you early is set almost entirely by how the last person was treated for telling you early.

Ask a question that makes doubt easy to state: what part of this is still unclear. Then respond to the answer with logistics rather than disappointment. If you are the one holding the doubt, name it now, while it is still small enough to be useful.