Is not the ideal choice. Google search list former use of that abbreviation with a very bad connotation:
I normally do such a quick search to avoid awkward situations.
I had some fun doing the background check for “btf” before I drafted [Draft] Motion to join BTF - masterOfDisaster and wanted to be elected as member 
…I might have printed a certificate of membership to show it to others, lol
Not bad!
On the contrary: rather good - especially compared to SS!
We can still use ‘Stable Supply’, but we can use NCN (NuCoin) for the abbrv. So BTC-NCN.
How about SQ Series (Stable-Quantity)? I like the idea of having a Q anyways, it’s memorable. So, SQ Series for fixed-supply NuCoin products, and SV series for our NuBit products.
Interestingly, nucoin.com redirects to Kraken’s exchange. I wonder if they would sell us that domain name.
NuCoin sounds great and it matches the existing naming structure for major cryptocurrencies. I like it.
Edit: Bitcoin-NuCoin is a bit awkward due to the double “coin” and varied capitalizations. What about B-NuCoin (B-NCN) for the Bitcoin-inspired product? That matches the naming convention for NBT products, such as US-NBT and CN-NBT.