Apparatus related to dual connectivity

A secondary base station for a dual connectivity which

• communicates with a terminal apparatus over a secondary cell group (SCG) bearer, comprising:
• a transmitter configured to transmit, to a master base station which communicates with the terminal apparatus over a master cell group (MCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station which communicates with the terminal apparatus over the SCG bearer;
• and
• a receiver configured to receive a second message indicating a rejection of the release, the second message being transmitted by the master base station in response to the first message,
• wherein the second message includes wait time information indicating a time period for waiting before the secondary base station initiates a next release procedure.

A method of a master base station for a dual connectivity which

• communicates with a terminal apparatus over a master cell group (MCG) bearer, comprising:
• receiving, from a secondary base station which communicates with the terminal apparatus over a secondary cell group (SCG) bearer for the dual connectivity, a first message requesting a release of the secondary base station;
• and
• transmitting in response to the first message, to the secondary base station, a second message indicating a rejection of the release,
• wherein the second message includes wait time information indicating a time period for waiting before the secondary base station initiates a next release procedure.