Hello aspirant,

Provisional merit list is not the final one it is just an approximation ranks according to the previous years marks and cutoffs as your final rank may vary alot also coming to the free seat scheme it is given on the basis of various factors such as category, gender, family annual income, cutoff,rank, availability of seats, merit,etc. So it totally depends on the time and councilling body whether you get that seat or not. 

Hope this helps

If any queries feel free to ask

All the best!!

Regards.