Should I modify my data to reflect time dependence of my rules?
Maybe I misunderstood something, but if you have feature vector with N features, it would be ok to add one more feature reflected the time. Then there could be two instances with the same first N features, but the different (N+1)-th and as a result the answer will differ too: "yes" for one year and "no" for another. However, for some instances answer will stay the same, which is also possible. So, I guess your idea might work, if there's actually some connection and meaningful "pattern" in real-life data.