Estonian harbour Baltiski became a free port according to the Weekly Intelligence Summary No. 43 dated 29 October 1921

An item reported that the harbour of Baltiski [Paldiski, Estonia was converted into a free port and dredged to a depth of 23 feet to replace the port of Reval [Tallinn] in the period she was frozen up to prevent stopping Estonia’s transit trade.

Source

The National Archives, Kew Gardens, England CAB-24-129-57