Systems, devices, and techniques described herein relate to migrating a communication session from a path including a stressed user plane function (UPF) to a path including a replacement UPF. A communication session may traverse a first path including the first UPF. After establishing the communication session, the first UPF may be determined to be stressed. In response, the communication session can be proactively migrated to a second path including a second UPF. According to various implementations, the existing communication session can be maintained during the migration, thereby substantially eliminating interruptions caused by the stressed first UPF.