Whoever is in Mina then he assumes Ihram from there
Question:
What is the ruling concerning whoever was in Mina before the day of At-Tarwiyyah (the 8th of Thul-Hijjah)? Does he enter Makkah and assume Ihram from there or does he assume Ihram from Mina?
Answer:
Whoever stays in Mina then it is legislated for him to assume Ihram from Mina, and all praise is due to Allah. There is no need for him to enter into Makkah. Rather, he says the Talbiyyah from his place for Hajj when the time comes.
Source:
Shaykh `Abdul-`Azeez Bin Baz
Fatawa Islamiyah Darussalam Vol:4 page no. 120