I am a US citizen, and I have an open jaw flight on Finnair from Helsinki to HKG in July

then return Shanghai to helsinki in Aug. I am planning to travel around (non-china) Asia for 5 weeks, and fly from Taiwan to Shanghai on the last 3 days of the trip. I will likely fly Air China from TPE to Shanghai, on a different ticket from the Finnair flight I have back to Europe. Am I still eligible for Transit Without Visa in Shanghai? The main issue is that my inbound to Shanghai and outbound to Europe are 2 different airlines, 2 different tickets.