In general Western fighters have a "initial" service life of 6000 h, Russians less coz less good quality* more cheap also and pilot flight less beside last Su-27 modernised in SM3 ordered will have a service life of 3000 h for 20 years this corroborates that.
And Russians/Soviet have always give priority to the number and less to quality.
A more long service for Chinese Flankers maybe ? but not for J-11/A build with Russians kits and many difficulties some return to Komsomolsk.
So, if there are 5(?) Su-27//J-11/A units left at 24 jets each and a total of 105(?) J-11/A produced, that means all that is left are some -27UBK from the third batch to support training in those remaining units plus perhaps form one type training / conversion unit?
That would mean 20+6 & 16+6 SK/UBK are retired. Essentially all of the SK. If each one of the 5 units retains 4UBKs, that leaves 18 from the last batch for one training unit.
Yes 105 J-11 whose 45A initialy a license for 200 and finaly J-11B...
Only the 1st lot retired 20 Su-27SK + 6 Su-27UBK remains exept losses in this case 18 Su-27SK + 34 Su-27UBK.
For J-11B i have 120 but for 2/3 years ago and i found now ~ 170 ? can be good, 4/5 lots of 20/24, 2008/2012 or 2013, after ?
These last years much more difficult for find, first years 1992/2003 i had infos easy ( without internet i have since 2010 ) first J-10 include more easy also coz import fighters, Russians Flankers as Su-35 now, begin more difficult after and from 2/3 years infernal they talk much less... !