Dotted Notes vs. Tied notes (a toggle between options ?)

I’ve been making some nice melody lines with keyboard input (qwerty variety) when Dorico started to change behavior.

For while I was getting dotted notes… but now that’s changed over to the tied equivalent notation.

Instead of of a Quarter note + the Dot. . . I’m now getting a Quarter Note tied than an eighth note (as an automatic formatting).

Anybody know what I did to trigger this change in behavior?

Probably the difference is simply the nature of the rhythms you’re writing. Dorico will use dotted notes if the options in Notation Options are set to allow them in the specific circumstances of the rhythms you’re entering. You should review the settings on the Note Grouping page of Notation Options to see if they are set up as you want them to be.