It seems to conflate people's names with words in a sentence, e.g. "I'm crossing the Bridges." Could just be confirmation bias, but whenever I notice that problem it tends to be a name in my address book.
Reminds me of how it capitalises "El Niño" as if I was talking about that climate thing, when I'm just trying to say "the kid" in Spanish.
Interesting. I was going to suggest that was from using the English rather than the Spanish keyboard but I just saw my iPhone do that on the latter as well.