Advice regarding my probate case

My family has recently filed a case of probate of will at Saket court, Delhi. There are 2 brothers, my father being the elder, and 3 sisters(all married with family).The will is about our 2 floor home - uncle staying on the ground floor and my family on the first floor. The will was made by my late grandmother and it says that the rights of the ground floor belong to my uncle, whereas the right to the first floor and construction right of a second floor and above belong to my father, and that the sisters do not have any part in the property. My uncle has objected to it in court which we expected.However, in the last two month, my aunts have not received the court notices and although the aunts had first said that they will keep out of it and give the NOC, we are not sure about it now. Also, some lawyers are suggesting us we should have just straight away started construction of the second floor as the will entitles us for the same, and in case of any objection by my uncle, then file a injunction/partition suit. So can we withdraw the probate case? If we can do so, can we later file another probate case? Does the court charge for withdrawing the case? Is there a better way for us to be able to construct a second floor without filing a probate case. Any help would be greatly appeciated! Thanks, Prannoy