Is it permissible to continue fasting to make up for Ramadan if the second day of Tashreeq coincides with it, or must one complete the fasting after the days of Tashreeq?

The Days of Tashreeq are the three days following Eid al-Adha (the 11th, 12th, and 13th of Dhul-Hijjah). Fasting on these days is forbidden, based on the saying of the Prophet (peace be upon him): "The Days of Tashreeq are days of eating and drinking."

The only exception to this is the Hajj pilgrim performing Tamattu' or Qiran who cannot find a sacrificial animal; it is permissible for him to fast them.

As for making up missed Ramadan fasts, or voluntary fasts, or fasts vowed as an oath during these days, it is not permissible. And whoever fasts on these days to make up for Ramadan, their fast is not valid and must be redone. Consecutive days are not required when making up Ramadan fasts.