IDOC: Which deadlines do I trust?

The earliest deadline on college websites is Feb 15th, while on the actual IDOC website the earliest deadline is March 1st. Should I be asking each individual college that I applied to?

Use the deadline published on the college website.

More clarification: All colleges say Feb. 15th on their websites, but they all have March 1st deadlines on IDOC. I know one college says Feb. 15th is the “priority deadline,” meaning they will send the financial aid decision with the acceptance letter, but the others don’t say anything.

Use the deadline published on the college website.