Supervisor to a team

You are a team member on a major project for a defense contractor. Your supervisor has just called an “urgent meeting” to discuss the current problems with the project’s progress. The project is months behind and slightly over budget. Most people feel it is due to the lack of resources (your project is the third priority). The meeting is in 30 minutes and you have no additional details as to the meeting content. Your supervisor routinely calls meetings with little or no warning, and then expects various employees to brief their portions of the project. When employees cannot brief their sections, the meeting is often canceled and rescheduled for after normal working hours to allow “time to better prepare (words of your supervisor).” You have had enough, you decide to email your supervisor and recommend a better way to conduct the meeting (be tactful).