In my experience, this behaviour may be caused by localization of your device/OS/browser. I'm not entirely certain how the end result is determined, though. Even if you specify an explicit language code, it may be overridden or fall back to default.
I think if you use a custom format that only uses numbers (like 'dd mmmm YYYY'), you can get a consistent behaviour.
Be wary when using the text options though. For example, in some of my apps I use 'Text(date, "[$-nl-NL]dddd dd mmmm yyyy")' to display a date; but I observed that if my browser language is set to English, it doesn't display the date in Dutch. And if I view it on my device, and the device language is set to English, it also displays the English text.
