BlackBerry has suggested for users to head in the direction of the right BlackBerry World listing of the Facebook app, where one can then perform the update download. Doing so and installing the update would transform BlackBerry’s native Facebook app into a link which will guide you to the web-based version of the site instead.
The BlackBerry support page does mention, “Those wishing to continue using Facebook are encouraged to move to the web-based experience which will provide the most feature rich alternative.” This would also mean that BlackBerry Hub integration is no more on Facebook after the update, in addition to “BlackBerry 10 smartphones will no longer have the ability to share items like pictures and videos directly to Facebook using the Share icon.”