If they're using ironhax, I heavily suggest trying to be patient for a bit (since there is no reason to update from 9.9 other than eShop access) as smealum works on this.My friend who has N3DS 9.9 N3DS wants to update to 10.2. How can I set up Ironhax that will work on 10.2. I heard some people updated from 9.9 to 10.2 and Ironhax stopped working, which ended up requiring a CN copy for Ninjhax 2 to reinstall Ironhax.
if your only reason for updating is eshop access : DONT. not yet anyway. help is on the way for 9.3-10.1 users !
— smea (@smealum) October 21, 2015