Daily and Weekly reports - dates

Hi

I enabled the Daily/Weekly/Monthly reports.
I've noticed that in the Daily and Weekly reports, the subject dates are not the same as the dates in the contents of the reports. They seem to be a day off.
Is that by design or an error?

Example: Daily report
Email Subject: Anturis: Daily up-time report for 10 Dec 2014
Email Content: Thu, 11 Dec 2014 (UTC)

Example: Weekly report
Email Subject: Anturis: Weekly up-time report for 30 Nov 2014 - 07 Dec 2014
Email Content: Mon, 01 Dec 2014 (UTC) - Sun, 07 Dec 2014 (UTC)

Please let me know.
Thanks.