The Continental Congress adopted the Lee Resolution for independence on July 2, 1776, before the America250 milestone.
Richard Henry Lee of Virginia introduced the resolution, which stated that the colonies should be free and independent states. Congress approved it on July 2 after debate and after several colonies received authority to support independence.
The Declaration of Independence followed on July 4. Its purpose was to explain and justify the decision already expressed in the Lee Resolution. This is why John Adams believed July 2 would become the major annual celebration, although July 4 ultimately became the recognized holiday.
The two dates are therefore related but not interchangeable. July 2 marks the formal independence vote, while July 4 marks adoption of the Declaration's final text.