In DC mode, The SeNB is primarily responsible for allocating radio resources of its own cells. At least one special cell in the SCG has configured uplink with PUCCH resources. Special means a cell in SCG group having PUCCH resources. I am not sure whether special cell is also called PScell or not. If its PScell ,you can check link below. https://tech.queryhome.com/168250/lte-what-primary-secondary-cell-pscell-and-which-context-used
What is the possibility of cross carrier scheduling in dual connectivity?
How was deployment scenario for Dual Connectivity. When MeNB should trigger SCG bearer or split bearer?
