[VV2.1] no faction leader after tag changing

[mate0815]

it seems, the change_tag command works not for all values.

i started as atrebates. after i fullfilled the gallic nation mission i changed the nation tag to GAU. some times later i changed my government from tribal to republic. but there are no faction leader shown in government screen and no bonusses for faction leader...

so i took a look at the savegame and found this:

GAU = {
....
    military_party={
        country="ATR"
        strength=9
        leader={
            id=591691
            type=44
        }

    }
    mercantile_party={
        country="ATR"
        strength=26
        leader={
            id=591963
            type=44
        }

    }
    religious_party={
        country="ATR"
        strength=17
        leader={
            id=590994
            type=44
        }

    }
    civic_party={
        country="ATR"
        strength=21
        leader={
            id=591338
            type=44
        }

    }
    populist_party={
        country="ATR"
        strength=27
        leader={
            id=591543
            type=44
        }

    }
...
}

after i replaced the ATR tag to GAU manually, all works fine.
any way to let the game do this for me (and the others)?