Keras: Is there a need to reload the model if I train for 10 epochs multiple times?
Can I compile the model one time and fit for 10 epochs, perform the metric and fit again for 10 epochs

Yes, absolutely.
The model will keep the training weights between calls to fit(). You can call this as many times as you please.
I am training a model and want to use the mAP metric. For some reason the tensorflow mean_average_precision_at_k does not work for me, but the sklearn average_precision_score works.
How can I have access to the keras's model outputs to perform the sklearn metrics?
Can I compile the model one time and fit for 10 epochs, perform the metric and fit again for 10 epochs? Or do I need to save the model and reload it every time?
Thank you