[Why would they add specimen to notes that are already in existence? One Day After The United Nations Security Council meeting yesterday. hmmmm.]  https://cbi.iq/page/89

Unknown, could be, a number of reasons … Perhaps, the photos and description/s of notes on the CBI site will be used as an aid/s…Normally a small run of banknotes designated with the word (specimen) are distributed to foreign exchanges and Central banks, as an aid in recognizing currency from a different country, and… used as an aid in detecting counterfeit currency…Or, a means of preventing the use of depicted notes from being copied for reasons other than their intended use.