To specify the observing settings:

Choose Webbla > Preferences.

Click General.

Choose the settings you want.
Look for website updates You must check this button to activate the automatic website observing.
Continue to check website until changes are over: Set a level to stop to check websites after Webbla recognised changes over a defined level. This will reduce network trafic if you are not interested on the level of changes on a website.
Not more than every: You can set a minimum time period Webbla will waite before he checks the same website again.