During the Chinese Lunar Mission hundreds of VLBI observations have been carried,we re-analysis all the quasar observations which used to calibrate the satellite observables.In each session there is at least one scan lasting about one hour,we use these data by splitting them into different time intervals and doing self-calibration each other in phase-referencing style to investigate the relationship of differential delay and different "time-switching".In this report we will present our primary result.