Your original jewelry should stay in until you are ready to downsize, which for a standard helix piercing and most cartilage piercings, is 12 weeks.
Also question is, what happens if you don’t downsize piercing?
What if I don’t downsize? I‘ll be honest- you might be fine! You might also end up with big bumps, irritation, or your piecing migrating and becoming crooked. All these things can cause the piercing to fail and need to be removed.