I have, over the years, gravitated towards telling everyone in my teams as much as I possibly can at all times. I use top-down information sharing like your scenarios as a chance to connect my teams (which tend to be infrastructure and futher from the core business) to the business and their needs.

Any system of information sharing that requires me to remember what and with whom I shared specific bits of compartmentalized information is ultimately doomed to fail. You'll forget who knows what and eventually screw up and then you look like a manipulative middle-manager for withholding information.

Unless there's a clear reason not to share (layoffs, acquisitions, etc.), I share.