duration visa

Hi!
I have a question regarding the duration of the 144 hours twov. on the website it says the visa starts 00 the following day. I will arrive in beijing from Sweden at 945 on the 18th of may and I plan going to Tokyo on 23rd at 925. I guess it will be OK since it is within 144 hours and that the visa actually ends at 00 24th?
regards,