Cryptopia has completed the 0.15.4 upgrade! Phew! Thats always the most stressful bit for me. I'm following up with Tradesatoshi. Remember, don't use novaexchange, they're closing anyhow so no need to update them, and we warned everyone to get their coins out ages ago.
Now is _definitely_ the time to upgrade to 0.15.4 if you're still running an older version. At block 23500 we should see difficulty adjustment start to function normally...finally.