I agree with the above answer. The barn bar is open weekends.
Rancho Las Lomas is an event venue so it's open when they have an event. The barn bar I believe has a specific schedule for when it is open but you'd probably need to contact them to get hours for that. There's some info on the Rancho Las Lomas facebook page and they do answer questions there as far as I know or you could call them.
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