Adding 10 minutes to current time - issue at midnight

Hi all,

In one of the spreadsheets there is a need to have a 'action at' field.

This is the next five minute time slot between 5 and 10 minutes in the future (eg 10.51 -> 11.00 , 1.56 ->2.05 etc)

this is fine using this formula

ROUND(((DATE_TO_USE+TIME(HOUR(NOW()+(5/24/60)),ROUND(MINUTE(NOW()+(5/24/60)),0),0))+(2.5/(60*24)))*(12*24),0)/(12*24)

'DATE_TO_USE' is the day we should use (changes after 23.50)

IF(AND(TIME(HOUR(Update_StartTime),MINUTE(Update_StartTime),SECOND(Update_StartTime))<=0.999988426,TIME(HOUR(NOW()),MINUTE(NOW()),SECOND(NOW()))>=TIME(HOUR(Update_StartTime),MINUTE(Update_StartTime),SECOND(Update_StartTime))),TODAY(),DATE(YEAR(NOW()),MONTH(NOW()),DAY(Update_StartTime+1)))

these combined work fine for every period from 00.00 to 23.54.59 but in the next five minute period point to 00.05 on the current day (as opposed to day + 1)

Can anybody see why this is?

Thanks in advance

Alex