How can I change Timing Advance in srsENB after RRC Connected?

[Kong-TaeHyeon]

Situation

I want to change TA in srsENB After RRC Connection connected. So I find a method (allocate_ce, set_ta in stack/mac/ue.cc).
So, I change code.

Excepct

I expect that UE is changed TA So, UE's message can't touch to the ENB.

Result

TA Value is not changed . . . .