Can COA directors have closed meetings without any notes?

Our community has 20 building each having a COA independent of the master COA. Each building has a member representing each building as a director on the master board. Then there is a mater executive board elected from the 20 directors of the master board. Question is can the executive board have closed meeting and not post notices of meeting and can the master board do the same? Not post notice on the association website or in a designated common area. This is a hot top topic because there appears to be an air of keeping information from unit owners in the community. bylaws do not specify closed meetings of kind. know about the 2 exceptions in Florida condo law about privileged information between lawyer and board and also when discussing personal information during board meetings. neither of which are during master board meeting since the developer turn over.