Time frame? Easy! What speed are you going to maintain? How many miles will your course cover? How many places are you going to stop? How long will you spend at each stop? Well, maybe not so easy - you're for sure the only two folks who can answer the question.
Otherwise, note which inlets are class A in case the weather
goes bad. Charleston is a great stop. I used to live at St. Simons Island, Ga. and really loved it. Golden Isles Marina at SSI is not convenient to anything, but they used to have a marina car.
The St. Marys' river inlet offers two great options: Head
North and anchor
behind Cumberland Island and dinghy
ashore to a National Seashore Park complete with wild horses, large sand dunes, mansion ruins, etc.; alternatively head
South to Fernandina Beach which has a couple of marinas
and a great revitalized downtown area with various bars, restaurants, and art gallerys. Don't miss the Palace Saloon
Last but not least, St. Augustine's more fun for a sailor than Jax.
Have a great trip!