When a process is running or has completed and there is not enough disk space to proceed, Metashape will pop up an error dialogue box that warns the user that there is no disk space, at which point the action has 100% failed with no way to retry or resume.
Could you put a Retry\Resume button on this dialogue type, so that we can free up disk space and carry on without losing the work already done, it could be that 20+ hours of processing has just completed and is being lost due to something that can be easily dealt with.
After the user has freed up disk space all Metashape has to do, is retry that action it was stuck on, and the process would continue without any loss.