About 70 to 80 years ago my great grandfather had donated a piece of land to our Community and had made it waqf to be used as a cemetery.

Question

About 70 to 80 years ago my great grandfather had donated a piece of land to our Community and had made it waqf to be used as a cemetery. It was not being used as a cemetery then because we already had one which had plenty of space. After the independence of our country the government brought about a law that this land could not be used as a cemetery. Hence the leaders in our community contacted the family requesting permission to nullify the waqf, changing it from cemetery to building houses for the community members. The family in conjunction with the community leaders consulted the ulema then and they were advised that waqf can only be nullified by the one who has made the waqf, and nobody else not even the heirs of that person. However keeping that in mind and that since there was no need for the Qabrastan, the ulema said that the land could be used for construction of the housing for the community members. A few years ago this issue has come back haunting us as the family that it was not rightly done then. We have been told that a Waqf cannot be broken under any circumstances and if the conditions are not favourable then the community together with the family should invest the value of land received into another piece of land and make it waqf for a cemetery. My question is: do we have to do that? Or whatever our elders and community leaders did then in consultations with ulema was correct?