A network node and method performed thereby, for enabling determination, by a prediction function network node, of a change in QoS of a communication session of a UE. The method includes obtaining information related to the UE communication session, the information including an ID of the UE and an ID of the communication session. The method further comprises determining the target serving cell of the UE and providing the obtained information and an ID of the determined target serving cell to the prediction function network node, thereby enabling the prediction function network node to determine new QoS of the UE communication session when being served by the target serving cell. A prediction function network node and a method performed thereby, and a user equipment and a method performed thereby are also disclosed.