Upload images to GCS and link URLs of all posts; AFTER return local server…

I would like to know if I can transfer all my files to the Google cloud, including the URLs so that the posts link the images with the files that are in the Google cloud; and then, after all the procedure is complete, start using my local server to store the new images?

That is, can I have old posts with images stored in the Google cloud, while new images would be stored on the local server so that new posts could use these new images stored locally?