25 Hour 30 Min Transit

Hello, I am aware of the 24 Hour Free Transit but I have two (2) separate layovers for my flight from Dhaka-Vancouver. The layovers are Kunming (12 hours 15 mins) and Shanghai Pu Dong (13 hours 15 mins). What should I do in this case ? Can I use the 24 hour transit in Kunming and just not leave the airport in Shanghai ?