Do we "need" flights and Hotel Booked

My husband and I are in Manila until Feb 26th - we then head to Bankok and have return flights from there on March 27th to return to home in Canada.

Our Plan is to leave Bankok - Hanoi - China - we're not sure if we'll start in Beijing or Shanghi - we'll only be in China 10 days - since we like to just book flights as we need them, we're having problems determining an exact date of entry (booking flights and hostels and unable to get refunds/make changes)

Can we go to the Chinese Embassy here in Manila and give an approx. date of entry?