There's an interesting article in The Blanket by Des Dalton who argues that while Fianna Fail,Fine Gael,The Worker's Party and the Provisionals may attempt to claim the right of celebrating the centenary,only Republican Sinn Fein are the sole inheritors of the SF mantle.

Part of his argument is that in the last 100 years,"numerous groups have broken with Sinn Fein and subsequently were absorbed into the partitionist system north and south."

Are Republican Sinn Fein not aware that the founder of Sinn Fein,Arthur Griffith,was one such individual who signed up to the partitionist system which RSF oppose?
Perhaps then 2017 might be a better time for RSF to celebrate its centenary?
I think it would be far better for all these parties to use the centenary to honour Arthur Griffith since the Sinn Fein he founded was quite different to the one which followed the post-1916 Sinn.