// TODO (Kal): Setting the state to kCloning below means that if cancelClone was called we will
// send a cancellation command to the recipient. The reason to limit the cases when we send
// cancellation is for backwards compatibility with 3.2 nodes, which cannot differentiate
// between cancellations for different migration sessions. It is thus possible that a second
// migration from different donor, but the same recipient would certainly abort an already
// running migration.

The above is from migration_chunk_cloner_source.cpp
Creating this ticket for kaloian.manassiev@mongodb.com to avoid blocking merge to a PR.