I want to catch the Rotom in Platinum but it is really early here so I was thinking of setting my clock to catch Rotom then AFTER I catch him switching my clock back so will this make so all other time based events will happen?
Yup that will work. time events like that work are based on the DS's internal clock. If you change your time then it will think that it is evening and you can catch Rotom!
Source; experience
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