As we've now rolled into 2018, many folks have been letting us know their WhatsApp client on BlackBerry 10 is still working despite WhatsApp announcing app would no longer be supported as of December 31st. You'll want to hold off on the celebrations and thanking of WhatsApp however as it's really only a matter of time before the app stops working.
Once the date passes Dec 31, 2017, the app will go into "deprecation" mode. It will still continue to function for a short grace period, but some behaviors will change. Most importantly, you will no longer be able to re-register your account with the app. That means if you delete and reinstall it (or install it on a different phone), it will no longer allow you to verify your phone number and complete the setup process.
After the grace period, which is approximately two weeks after the published date, the app will go into "expired" mode. At this point, it will stop functioning as a usable WhatsApp client, and thus will no longer connect to our servers. (Around this same time, our servers will stop allowing the client to connect as well.) However, once it is expired, the BlackBerry 10 client app may still allow you to access your existing message content on your phone. This behavior should be similar to what was seen by everyone who forgot to update their app the last time our published expiration date had passed.
In other words, just because WhatsApp didn't go kaput on December 31st, that doesn't mean anything has changed. The BlackBerry 10 client is just a dead app gasping its last breaths of air. As we've mentioned before, you should really being making all efforts to move from the native app as the longer you wait, the more chance there is that you won't even be able to export your data as it requires a connection to WhatsApp servers.
Additionally, since people continue to ask, you can install the Android version on your BlackBerry 10 smartphone alongside the fixes that allow for sending multimedia as an alternate way of keeping WhatsApp working or move into a new smartphone such as the BlackBerry KEYone or BlackBerry Motion where WhatsApp will still be supported.