L.P.
I always throw Sunday parties. It's a day to relax and not plan anything so we always plan dinner at mom's anyway. I always text everyone to give a "save the date" so that way everyone knows ahead of time when the party will be. Details to follow later and by later, invite standard for a party is 2 weeks. Weddings are 2 months. I think anything too early and people forget. Too late and they make plans.