Yes, she can claim the exemption u/s. 54F.
The condition to be satisfied to claim the exemption is that the residential property should be purchased either within one year prior to the sale of the property (on which LTCG is earned) or within two years(Purchase) or three years(Construction) from the date of sale of the property.
Since the flat has been purchased within one year prior to the date of sale of the land, the exemption u/s. 54F would be available.
I hope this answer satisfies your requirements.
CA Hunny Badlani