The present invention relates to a method of, and device in the form of a radio access network supervising entity for, adapting to delay in a communication link established between the radio access network supervising entity and at least one radio base station communicating with a mobile terminal. The method comprises associating a target Connection Frame Number (CFN) to each transmitted data frame, said target CFN being calculated by offsetting an expected CFN with a counter value corresponding to a current communication link delay, repeatedly determining delay of the communication link, and adapting to the delay of the communication link by adjusting transmission time of the transmitted frame, and/or adjusting the target CFN of the transmitted frame, said target CFN being calculated by offsetting the expected CFN with a counter value corresponding to a determined new delay.