I used the term "scheme", which refers to a broad trend in subsystems upgrades. For example, both Su-35 and the J-11D feature avionics upgrades, extensive airframe enhancements, upgraded EW/ECM suites, and engine upgrades. This in no way implies that the subsystems themselves are the same or even that the spectrum of upgrades are exactly equal, but rather that the two aircraft focus on the same areas of improvements.
The Chinese have been developing, designing, building, and retrofitting Flanker variants for over 17 years now; there is no reason to doubt their familiarity with the Flanker airframe.
Fair enough, but my point was that the J-11D should be very similar to the Su-35 in this regard, thus ruling out the possibility that the Chinese are buying the Su-35 (again, assuming that rumors are true) due to a gap in capability. My post was specifically referring to the subsystems aboard J-11D/Su-35, not necessarily the maintenance requirements for them, which depends on a host of factors beyond R&D and manufacturing.
I'm not sure what you mean by "verification" or "validation", but I agree, the Chinese enginers and PLAAF brass are probably very eager to compare notes with their Russian counterparts, especially when they plan to operate domestic fighters that are very similar to the Su-35 such as the J-11D/J-16.