Not sure what to do, seen this post & seen this link:
http://www.perfectly-nintendo.com/animal-crossing-new-leaf-new-update-available-japan-ver-1-5/
I'm in the UK, so followed the info on 'perfectly-Nintendo' site - ie I could just link to my game (internet connected) and I should be prompted to update - I wasn't, I just entered the game. I was expecting a message similar as to what happened in HHD.
So I went to Eshop and yes there is an update, v 1.5 - but I don't know for sure what would happen if I downloaded this, given I am on V 1.4 currently.
I could not see two versions of 1.5 as implied by the 'perfectly Nintendo' site. Maybe the link picks the right one for you automatically? Yeah, maybe, I'd prefer something more definite.
There is no info as far as I can see on Nintendo UK site for updating 'acnl welcome amiibo V1.4' to 1.5, (albeit I find that site hard to find anything on, so maybe it is there?).
I'd 'phone Nintendo but I guess I would enter a long queue to get to speak to someone who knows no more than I do currently.
Hence for now, I'm holding off updating until I see more info.
Edit: I have a new acnl game cart on pre-order with Nintendo UK store, a cart with the update included.
It should have been in the post yesterday as today (for the UK) is its release date - and I'm still showing as 'processing' .
Not sure if this is just my luck, or whether there are problems/too much going on for Nintendo: Pok?mon, Black Friday/ V1.5 update - I don't know.