中国香港采购需求：国际学校，国际K12学院，国际私立学校，独立寄宿学校，私立学校，英国学校

I'm currently living in Hong Kong with my family and planning to relocate to Guangzhou around July or August this year. I have two sons: the elder is 7 years old and the younger is 5. They've both been attending an international school here and have adapted quite well to the curriculum and environment. I'm very interested in exploring educational options for them in Guangzhou, particularly the British International School (BIS). Could you please provide information on the admission process and whether there might be available slots for my sons? It would be great to understand if their previous experience at an international school would be beneficial for their application. Thank you!