We have absolutely no idea what they plan to do at quarterback in this draft. Yes, "logic" might seem to suggest that signing Philip, trading away their 1st round pick, and keeping Jacoby at a starter's salary just to be the backup would mean they aren't looking to take a quarterback in the draft, and furthermore that they plan to let Jacoby learn from a Hall of Famer for a year or two so he can take over down the road, better than he was before.
But that could all be just a smokescreen, and they plan to take a quarterback with their first pick, maybe even trading up to do so, dump Jacoby after the draft (or possibly include him in that or another draft day trade), and let the rookie back up and learn from Philip for a year or two.
Or they could be just keeping every chip they can, seeing how it all plays out while being ready to use those chips as the events and opportunities offer themselves up. Which is actually exactly what every team should do.