Are there any risks on forcing the System Date Back & Forward?

Hi,

I have MySAP ERP 6.0 installed on ISeries V5R3M0 which will be in Production in February

By that time, all transactions beginning from Jan/01 will start to be registered in sequence till the Feb/xx is reached, so this date and so on will then be normally worked

Question is what should be taken in mind, what may this implicate to system functions, are there any SAP recommendations regarding this or if there's a better way to proceed?

Thanks