I think Fri/Sat would work the best for the most, as far as days of the week goes. If it's an all-day party, even better!
Like I work weekends but could eavesdrop during work (as it's slow) and join in properly once I'm home in the evening, though I'd likely miss the Europeans. Buuuuut if it was a Friday I could likely be there much earlier.
Although the world doesn't revolve around me so er, tbh dunno what works best. I'll throw out some dates then
Friday 12th, time - ALL DAY
Saturday 13th, time - ALL DAY
Friday 19th, time - ALL DAY
Saturday 20th, time - ALL DAY
Friday 26th, time - ALL DAY
I'm being biased and skipping the last saturday because I'd literally be gone all day and most the night