Scheduled Signatures and Banners

We need the ability to schedule signatures and banners to activate and deactivate based on specific dates and times.

Use cases:

• Holiday banners (e.g. display during a holiday break period)

• Sale/promotion period banners

• Seasonal email signatures (e.g. "Happy Christmas" or "Happy New Year" that activate and deactivate automatically)

• Time-sensitive campaigns across the organization

Currently these changes require manual updates, which is error-prone and creates unnecessary work for MSPs managing multiple tenants.