[Avodah] bat mitzva "bo bayom"

[menucha]

I am wondering if there is an inyan to have a seudat bat mitzva
(obviously for those who hold that a seudat bat mitzva is a seudat
mitzva) on the actual birthday.  My feeling is that since there's not
much else the girl can do on that day to show her reacing mitzvot (yes,
I know she can take challah, or tovel dishes etc.- ) that it seems more
important to have the seuda on the actual day, but i'd like to hear
other peoples reactions and sources.
thanks,
menucha