Answer:
No it is not Christmas day
Step-by-step explanation:
On the eve of Christmas day, is not Christmas day. its called "Eve" because it is a day before Christmas and such kind of days is 24th Dec., Christmas is always 25th Dec, so 24th is not 25th logically, it cant be counted Christmas day.
On such Holidays been done On Eve to Christmas, doesn't count for Christmas doesn't not mean that particular day is Christmas day, because 24th is not 25th and 25th is Christmas day.