Why there is no tier restriction of 6.13 patch on Chinese server ?

I'm on my vacation to China for 3 months.....recently I have already played to master tier and chinese server has updated to 6.13 patch.... but there is no tier restriction like what 6.13 patch of NA server did which was showed as "Reminder: From Diamond V and up, premades are limited to duos or trios. The entire premade has to be within a three-division skill range of each other." I can still make a 5 people team to go solo rank but I don't want to do so infact, i do this only because it's the best way to win. I've always wanted RIOT to restrict solo rank to at most trio mode and I'm glad they do so to NA server. WHY NOT UPDATE THIS ON FCKING CHINESE SERVER? There are boosters on this server everywhere and they boost at a really cheap prize ( like 30dollars to go diamond from plat 5 if 5 boosters boost their acc together when the first district 'ionia' charges higher to maybe 50dollars . In NA server, it charges almost 400 dollars to boost from plat 5 to Diamond 5) 5 people solo rank can not test the real LOL skills, some noobs can rank much more higher than they should be if they have strong friends. Please tell me what's going on about updating patch in China. BTW all chinese server have not cancelled team rank all the time, not like in NA, you cancel this mode at the beginning of S6 season but bring it back just now. I don't think this game should be different in different country.