Add new Labels to MLImageClassifier of existing Checkpoint/Session

Hey, i just created and trained an MLImageClassifier via the MLImageclassifier.train() method (https://developer.apple.com/documentation/createml/mlimageclassifier/train(trainingdata:parameters:sessionparameters:)) For my Trainingdata (MLImageclassifier.DataSource) i am using my directoy structure, so i got an images folder with subfolders of person1, person2, person3 etc. which contain images of the labeled persons (https://developer.apple.com/documentation/createml/mlimageclassifier/datasource/labeleddirectories(at:)) I am saving the checkpoints and sessions in my appdirectory, so i can create an MLIMageClassifier from an exisiting MLSession and/or MLCheckpoint. My question is: is there any way to add new labels, optimally from my directoy strucutre, to an MLImageClassifier which i create from an existing MLCheckpoint/MLSession? So like adding a person4 and training my pretrained Classifier with only that person4. Or is it simply not possible and i have to train from the beginning everytime i want to add a new label? Unfortunately i cannot find anything in the API.

Thanks!

Add new Labels to MLImageClassifier of existing Checkpoint/Session
 
 
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