You have two options for restarting the learner on the programme:
Clone the current programme to create the "restarted version" and then enrol the learner in the restarted version. The ILR token within the cloned programme will contain the aim references, so when the learner is added, a new ILR episode is created. You can then manually adjust the aims to ensure they meet the needs of the restart.
Alternatively, you can keep them on the original programme, add return aims to the ILR, and set the programme status back to active.