I would suggest announcing a date and THEN finding out who can attend. You should never base your date on who can attend unless there is another obviously larger event in the same timeframe.
Players scheduling for tournaments = good
Tournaments scheduling for players = BAD
Take it from someone who learned the hard way 
BAAAAAAAAAAAAAAAH… yup
Just trying to help
hrmmmm valid point.
Hoping to get together an impromptu just for fun Mini-Tournament
Marvel Super Heroes Vs. Street Fighter
Today 3pm and/or Tomorrow 3 pm if noone shows up.
Kozlov Mall food court
Round Robin or Single elimination depending on attendance
5$ entrance
Winner takes Pot minus cost of tokens
If noone shows up today I’ll be there tomorrow as well for another try.
Hope to see people there!