I'm pretty certain that what we are seeing aboard the DF-26 TELs are canisters for missiles rather than mock ups of actual missiles such as on DF-15B. The markings and little bumps on DF-26's canisters are very indicative that they are not missiles.
However the nose of the canister appears quite pointed, making me wonder just what kind geometry the missile has.
DF-16's TEL similarly has its missiles within canisters, but I believe that the canisters are more like enclosing covers, and open to allow the missile to be erected and launched.
DF-26 is more like DF-21 in that regard; its entire canister is erected to launch the missile within.