Smelly Jelly Questions

Hello all! I am new to this forum and to candle making. I want to make some smelly jelly but I was wondering, what happens to it as it ages? Does it "disappear" like those gel cone-shaped scented things you can buy for $1 at the drug store? Or does it just stay as is? If made correctly and with a good amount of fragrance, about how long does it last? What is the best size jar/container to use for smelly jelly?

Thanks!