It seems that you are working on PHP 7 support for about two years
UBB.threads 7.6.2 was just released on September 18, 2018. Once that was released, I began working around the clock (18 hour days) on php 7 support.
Php 7 support is happening. It's being tested right now. It required a lot of rewrite. All I can say is that you can see it working in the sites posted above. Those sites were updated with php 7.0 support less than 5 days ago.
We are also testing and resolving any issues brought with php 7.1 and 7.2. That's the best indicator of "soon" which I have right now.
Changing code and making it work for one single installation of UBB.threads is one thing, but when you take into consideration that there are thousands of installations of UBB.threads with varying board and server configurations, all using hundreds or even thousands of different custom forum settings and customizations, and that the current release is stable for all of those it would be irresponsible of us to suddenly make a change that would affect 100% of all updated installations without knowing if those installations would still work or not or if there will be data loss.
We want to test a bit longer so that large bugs don't suddenly come up, as has already been the case just testing from php 7.0 to 7.1 to php 7.2.