Ah, Amtrak. Being near the problematic Northeast Corridor, I feel your pain! This is a real and constant problem. When this happens I see successful team leads reaching out to Champions and Sponsors. They make sure that everyone knows the ramifications of each missed deadline and often make it public. This may require updating a Goal Statement to accommodate the new timeline. It may involve delayed savings and prolonged process issues. Often when the person sponsoring the project sees the repercussions, they will reach out to other leaders in order to refocus the straying team members. Champions and Sponsors need to play their roles too.