My question is that I am flying to Shanghai tomorrow from Jeju Island(South Korea).

I have a connecting flight but the next day at 6am to Taipei on the same Terminal 1 with China Eastern Airlines. I am a British Citizen, I wanted to know in this case will I be allow access to leave the airport for 10hrs wondering around SH then back to airport 4hrs before my flight?
Also, will I need to collect my baggage as it's the same airline?
Thank you
JJ