JOY I too didn't receive any update since the time you mentioned.
Generally update is rolling out in batches from past couple of updates so it's seen that all will recieve update in at least an week. If it's published today for some people than it will be available soon for our play store too.
If you just looking over this post of update
Then its most probably because he is an official member of sololearn as mentioned in his bio that's why he might have the update first which might be in testing version before roll out in public. Once testing complete then it will be available for all.
Looks like it is still under development (cos he is a backend developer at SL as already pointed out by Preity )
And is posted here as a teaser of new update which sololearn staff might be working on right now.