Messaging tracking logs filename format changed in Exchange Server 2013 sp1

Hi,

I have noticed that the file name format is changed for exchange server 2013 sp1.

Now it will have hh attached to it like

• MSGTRKMSyyyymmddhh-n.log;

• MSGTRKMDyyyymmddhh-n.log:
• MSGTRKyyyymmddhh-n.log.

So the "hh" will goes from 00 to 23 for single day.

So Lets say at 24 april 2014 first fill is created @7.30 AM, so the first file name will beMSGTRK2014042400-1.log. Now exchange server will create new file every hour by incrementing hh part of file name. Now the last file i.eMSGTRK2014042423-1.log will be created on 25 April 2014 at 6.30 AM.

I am not able to understand why exchange server is creating the file with old date on next day ( with 24 April on file name time stamp on 25 April).

And also how it will be decided to create the first file @ 7.30 AM.

Can anyone explain to me about this ? Why it is happening like this?

Thanks

Sandeep Gupta