“The proclamation extended the scope of Dunmore’s Proclamation, issued four years earlier by Virginia’s last Royal governor, Lord Dunmore, granting freedom to slaves in Virginia willing to serve the Royal forces. The new document, issued from Clinton’s temporary headquarters at the Philipsburg Manor House in Westchester County, New York, proclaimed all slaves in the newly established United States belonging to American Patriots free, regardless of their willingness to fight for the Crown.[3] It further promised protection, freedom and land to any slaves who left their master.[4]”
https://en.m.wikipedia.org/wiki/Philipsburg_Proclamation
It ONLY applied to slaves of those in rebellion. Is was NOT a general abolition of slavery as an institution.
Which means it was no different than Lincoln's emancipation proclamation. Lincoln's emancipation freed slaves only in the states in rebellion, and none in states that had remained loyal to the Union.
Philpsburg was a general emancipation because it didn't apply only to slaves who were willing to take up arms against the American rebels. It freed them regardless of whether they fought or not.