Here is what I know so far for the upcoming indoor season; Monday and Wednesday nights, 4 courts, 7pm-9pm, Saturdays 1pm-3pm. Also, court costs are $24/hr, so each player costs will be $12/session plus $1 for tennis balls.
My guess is that the first session would be Monday, September 9, 7pm – 9pm. That would mean that online signups would commence on Monday, September 2 at 7pm. Signups for indoor play are always 1 week in advance of each session. Signups for the first Wednesday session, September 11, 7pm – 9pm open Wednesday, September 4 at 7pm.