moderated Messages Read from Group's pages


I don't know if this has been addressed or not.
I know that the shortest amount of time that a message can be locked is 1 day if it isn't locked manually sooner.
Is there any way a selection could be added to have messages automatically  locked as soon as they are sent OR another option would be having a way to hide the messages from the members.
The reason behind my question.
My groups are Signature Tag Request groups. One group the offers are really short term offers like for the first 10 members who request.
Most members are getting the offer via email as my group is basically an email group and that is what we need it to be. Not a forum where they can read the offers from the group pages.
There are a few members who hang out at the messages waiting for new offers to come through and they are at an advantage to get their requests in quicker then anyone else and end up getting all of the tags that way.
While I am online almost 24/7 I can't lock the messages quick enough.
Thanks. Ilene  

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