Might be related to rumors that PLAN is planning to convert all of its land-based tactical aircraft units to carrier-based units.
I do think there's merit in that rumor. Take USN's tactical aircraft fleet for comparison: for the 750-sth super hornets, lightnings, and growlers, about 150 are used for training, and three CVWs operating 15 squadrons are deployed. For PLAN, let's assume 16 and 17 together are carrying about 20~30 aircraft at sea and that's already almost a third of PLAN's current J-15 inventory (if we take 60~70 as the total inventory). In addition, PLAN needs J-15s for training more and more new pilots.
Honestly, I am surprised there aren't at least 100+ J-15s for PLANAF's rigorous needs taking maintenance into consideration (such heavy use). We aren't even talking about reserve planes for "surge" usage which USN does keep a healthy number allocated to. So I do think converting units flying JH-7s, Su-30MK2s, J-10s, and J-11s to J-15s would help a great deal both for the commonality and robustness of the fleet.
On a side note if we assume the rumors are true, might it be a sign that J-15 or J-15B production will ramp up?