Items often have multiple dates you can assign to them, e.g. Due Date, First Payment Due, Milestone, Start Date, Defer Until, etc. Yet, how do you search for them?
Suggestion: Allow a {Type} field after the ‘!’, where the presence of an alphabetic character means that the date follows after the space.
For Example (using ISO date format, just to illustrate):
!start 180601 !due 180630 !milestone 180615 !report 180702 !presentation 180709