I'm designing the messaging for 2 types of scenarios. Planned maintenance, and unplanned downtime. in both cases, certain services on the app won't work, but the rest of the app will function as normal.
I particularly prefer the option that least obstructs the app. A modal window for a type of information referring to settings in the app itself is giving too much relevance to an internal activity that has nothing to do with the immediate/current activity of the user and can be interpreted as a negative warning. The modal windows in some cases works as a barrier between the user and the app.
By choosing the second option, I would also use less obstructive components.
- The info icon has no meaning when the information is already open or visible and framed
- In its place, I would put the app logo making implicit that it's an institutional information
- Text in red emphasizes its importance
- I would also eliminate the close icon, the X.
There are two options:
- Keep the information always visible, optimizing the text
- Or create a vertical slide visible when opening the application and hidden when interacting with it plus an icon to open it and see the content when the user needs it.
Use dismissible in-app messaging (version B). Users are more likely to close a modal without reading it when it interrupts their task.
You might want to lead with "Online booking will be unavailable" in your message -- put the impact to the user first, and the reason why (scheduled maintenance) immediately after that.