Dim mCol As Collection

Public Property Get Conn(ByVal ConnName As String) As ADODB.Connection
   Set Conn = mCol(ConnName)
End Property


Public Sub ConnectToBase(ByVal ConnString As String)
   Set mCol = New Collection
   Add ConnString, "Январь"
   Add ConnString, "Февраль"
   Add ConnString, "Март"
   '...
End Sub

Private Sub Add(ByVal ConnString As String, ByVal CustomBase As String)
   Dim ConnX As ADODB.Connection
   Set ConnX = New ADODB.Connection
   ConnX.CursorLocation = adUseClient
   ConnX.Open Replace(ConnString, "GeneralBase", CustomBase)
   mCol.Add ConnX
End Sub

Public Sub Main()
   ConnectToBase "Provider=... ;Initial Catalog=GeneralBase;... "
   'GeneralBase - это наше соглашение об именовании БД
End Sub

   rs.Open "select...", Conn("Январь"), adOpenStatic, adLockReadOnly, adCmdText

Private Sub Add(ByVal ConnString As String, ByVal CustomBase As String)
   Dim ConnX As ADODB.Connection
   Set ConnX = New ADODB.Connection
   ConnX.CursorLocation = adUseClient
   ConnX.Open Replace(ConnString, "GeneralBase", CustomBase)
   mCol.Add ConnX, CustomBase 'вот здесь
End Sub