A first communications device and a method therein for handling of active mode operation after transmitting data to a second communications device. The first and the second communications devices are operating in a wireless communications network. The first communications device transmits a first data transmission to the second communications device and enters a sleep mode. At a number of points in time, the first communications device temporarily wakes up from the sleep mode to an active mode for an active mode period. Further, the first communications device indicates, to the second communications device, a point of time of the active mode period.