Edit the file /etc/ovid/omf.properties on the Universal Server.  (It is recommended that you make a backup of the file first.)  In the file, find the option ovid.boormerang.recovery-window-minutes, which specifies how many minutes are allowed for reseting the password after such a request.  By default this parameter is set to 2 hours (120 minutes), as in this example:

ovid.boomerang.recovery-window-minutes=120

After making changes to /etc/ovid/omf.properties, you must restart tomcast (web messenger will be temporarily unavailable while this service is restarted).

pgpsysconf --restart tomcat

You may also wish to edit the email message that is sent to users to include a note about the amount of time they have to reset their password.  To do so, in the Universal Server web interface go to Mail> Message Templates> Recover Passphrase, add your desired wording to this template, then save the template.  An example of text that may be useful to add:

The option to reset your passphrase will exire 2 hours after this email was sent.