No, kage treasure do not work anymore that way.

Used to work that way in 2.0 but is since 3.0 that got changed to the current version.

People continue to say is 900-1800 because 99% of the people that went for both the super rares there did it in 2.0 and almost none has done it now.

If you are lucky could be you get sasuke even on your next rare draw.

Almost sure you get him within next 4-5 rare draws (you just need to hit the counter once and to not pull a lucky early random rare to get him, those are the conditions).

Is proven by the fact really a lot of people that went for 1 single super rare before 3.0 as soon as 3.0 was implemented got also the 2nd super rare just by going on with free draws there within the following month and is proven by the fact gnw treasure right now works that way too.

At that time there was some kind of uproar because many people that were close to 900 did not get their super rare at 900 (because the new mechanics required 1000 to unlock them and does not grant 100% sureness to get it a 1000. At 1000 the two super rares just go in the pull of the other rares, so could be you get the 1st one even at 1200) so they thought the counters were reset with the upgrade to the new version. The truth is that was simply changed the mechanics to the actual one, just that oasis was not aware of it at the time, so they did not explain it beforehand (was an unexpected change, like the fact we got advanced threads in sa with the implementation of myoboku trial cultivation or that bf ninja tools were nerfed with UT and charms implementation. If tencent do not tell to oasis there are side effects like those ones oasis do not know there are).