I'm hearing this movie will be based on the Tim Powers book, "On Stranger Tides". This one sounds like a prequal where Jack gets into piratery and meets Blackbeard on the way to finding the Fountain of Youth.

World Fantasy Award–winner Powers (Three Days to Never) demonstrates a precise control of complex narratives in this reprint of his rollicking and enchanting 1987 novel. Puppeteer John Chandagnac, bound for Jamaica to recover stolen money from his uncle, becomes Jack
Shandy Sparrow after pirates attack his ship and force him to join their crew.
Shandy's Sparrow's struggle to accept his new life grounds the story for readers, even as Blackbeard and vodun magicians whisk everyone away to dreamlike lands where the Fountain of Youth itself awaits. The chaotic sea battles sing, though at times key events happen so quickly that they get lost in the shuffle as Jack tries to comprehend where he's going and what's at stake. This dark fantasy tale will appeal not just to pirate fans but also to anyone who appreciates Powers's talent for blending the most unlikely elements into a brilliantly cohesive whole.