What is interim model

[Alikavari]

Hello
in part 3.2.2 of the main paper related to this CRAFT-Reimplementation, the authors say :
" When a real image with word-level annotations is provided, the learned interim model predicts the character region score of the cropped word images to generate character-level bounding boxes"
As far as I realized this model is used for generating character-level bounding boxes for word images that do not have character annotation.
My question is what is the interim model architecture and how is this model trained?
Is the interim model trained with the cropped words in the synth-text images?