I think they are doing simulated strike of bases on the Eastern side.
I doubt it.
After all, waypointing for LACMs (whether air launched like KD-20 or ground launched like DF-10) is quite simple. H-6Ks can remain hundreds of kilometers within Chinese airspace, and launch KD-20s on flight profiles with waypointing to hit specific targets on the east.
And that's only if for some reason there is a particular target on the east that can't be serviced with an SRBM or GLCM.
IMO this flight is more of a reflection of geopolitical signalling combined with a general increasing PLA ability/desire to project greater amounts of air power over the ocean.
This flight package w/ AEW&C, ELINT, multirole fighters, bombers and ASW aircraft, obviously reflects a multirole flight package between both the Air Force and Naval Aviation, and is a building block exercise useful for any sort of larger scale air operations in the western pacific in general, rather than necessarily being Taiwan specific.
If they wanted to do exercises that are more Taiwan specific (and to their credit I imagine they probably have) -- I would be sending up multiple flights of fighter CAP in ETC inside Chinese airspace just west of the strait, with representative exercises that can demonstrate the viability of theater-command-scale "alpha strikes" composed of bombers with ALCMs and AShMs, strikers with SOMs and AShMs, supported by a couple of AEW&C, ELINT, and EW aircraft, as well as tactical jammer and tactical recce aircraft and some UAVs... of course with PLARF SRBM and GLCMs (and maybe PLAGF long range MLRS) being involved in some capacity as well, and to carry out multiple rounds of such CAP+strike+recce/AEW "cycles" over a couple of days.
And the thing is it wouldn't require the PLA to fly aircraft over international waters or near Taiwan at all.
Given the effective range of KD-20s being anywhere from 1500-2000km, H-6Ks don't need to fly anywhere within a couple hundred km of Taiwan to begin with. Heck, even if H-6Ks were using the shorter range KD-63s, they wouldn't need to get closer than 200km.
If they are flying H-6Ks any closer than that, it is because they are doing geopolitical signalling and/or there are other scenarios beyond of Taiwan they are training for.