This is controlled at the Ambient Settings level and Autodesk provided no such format option (10+00).
However one could possibly achieve the desired effect with an expression and some fancy label style trickery.
What'choo talkin' 'bout, Willis?
In the other thread, you were saying this sort of thing is NOT controlled by the Ambient Settings. Of course, it's actually the same as the rest, where the Settings tree controls the settings of newly-created Styles, but existing Styles have this setting set inside the Text Components inside the Styles, and stuff inside Text Componenets in existing Styles can't be changed by editing the Ambient Settings.
The settings in the Settings Tree (e.g., Ambient Settings, or Settings -> Alignment -> Edit Feature Settings) will affect things like Tooltips, but not any existing Styles used to label Alignments or Profiles.
And there's no 10+00 format because it's called "1+00". You just use that format to get stations like 10+00. ...Or are you refering to forcing a leading zero, for stations like 05+00?