When listing schedules, those that are disabled are greyed out. When listing firewall rules, those that are scheduled are indicated with an asterisk. However, there is no indication, when looking at either the list of firewall rules or an individual firewall rule that it is assigned to a disabled schedule.
As for the firewall rule list, perhaps a different colored asterisk? Perhaps one/two asterisks to indicate an enabled vs. disabled schedule? Or, perhaps a new column?
When looking at a firewall rule, please indicate right next to the schedule name whether it is enabled or disabled.