In the Chinese calendar the year presently is 4648. You are asking for a day more than 2700 years ago. About 669 BC depending on the actual date it was introduced, which no one can say for certain.
The changes that have been made to both calendars would make this a very difficult calculation to make. In addition the Chinese calendar is a lunar calendar so the new year can start anywhere from late January to mid February which is another complicated calculation to make.
Nor did the Gregorian calendar exist at that time.
April = Gregorian calendar tamuz= Hebrew calendar siyue = Chinese calendar
The Dragon is the 3rd lunar month of the year or the month of April in the Gregorian calendar.
December has 31 days in the Gregorian calendar, as that is the calendar that we now use.
In the Gregorian Calendar the 11th month is November.
There is no month called Octo in the Gregorian calendar
July.
February
Not in the Gregorian calendar.
See related question
Febuary
November
Not in the Gregorian calendar