It will show only hours and minutes untill after 24 hours then it with show days hours minutes. The first part is the time of the report referenced to gmt or utc
Here is mine showing up for 5 days 7 hours and 13 minz:
page generated on Tue Jun 24 02:48:32 UTC 2014 UpTime: 02:48:32 up 5 days, 7:13, load average: 0.15, 0.15, 0.13