Do not agree with the above advocate.
Even before the Amendment Act of 2005, in West Bengal sons and daughters had equal share after the death of ther father as the state follows Dayabhaga law. So no difference here before and after amendment as far as share is concerned. Moreover ancestral property after succession is considered similar to self acquired under Dayabhaga law. So father can deprive anybody in such a property if he so wishes.
Section 6 of Hindu Succession Act (HSA), 1956 has no applicability in West Bengal as it is specifically written in the Act that it is for Mitakshara community only. So all brothers and sisters will have a share of 1/8 in your case.
But other Sections of HSA Act, 1956 which has applicability in West Bengal like Section 23 will have effect as directed by Supreme court.
So for daughters in West Bengal, they will get equal share as their brothers but they cannot enjoy such properties after their marriage or invoke partition until and unless succession starts after 9/9/05.
Also advice speaking to a good lawyer who is conversant with the local state laws. However I don't expect any change in opinion from what I have written.