target priorities

[Romaman]

Can anybody explain me something.
Id like to change target priorities for some units. So, lets take UEF T2 Heavy tank for example. I go to gamedata, open units file, search for uel0202 and open uel0202_unit.bp.
Then I look for 'weapon' section and edit second TargetPriority from, say, MOBILE to STRUCTURE. Then I save the file.
But nothing happen in the game. This unit attacks mobile enemies in range at first, and only then, when mobiles are not accessible, it turns to structures. So, my changes dosnt affect priorities at all.
What Im doing wrong?