What is webcal syn intervall?

Hello, what is the default sync intervall of a webcal calendar (webCal Account Type) in onecalendar?

Does the configured sync settings (1day, 12h, 8h and direct) also work for webcals? I dont understand, what "direct" means? When I configure "direct" under "Automatic synchronisation" setting, does this mean every 1 minute webcal is checked for new calendar entries?

Regards.