Given that it's due at the end of next week and you are getting multiple calls, that does seem a bit... needy.
The benign explanations could be that all NBL clubs operate off limited revenue/limited sources of revenue and of course in the off seasons those almost completely dry up, or tend to be fairly front and back loaded, i.e. memberships (new or renewed) perhaps mostly occur early (when they are opened for sale/renewal) and late (when the season is close), with a few very quiet months in between. Sponsorships and corporate sales are probably similar - early off season push and response and then late off season push and response. So there might just be an overall effort to spread the revenue more evenly through these off season months, with overall weekly revenue targets there that staff members are asked to hit and that's just filtering down from the 'big' of corporate sales to the 'small' of getting a member to pay up even a week or two early, just to try and get to that overall target number for 'this week'. It might not mean financial trouble at all, just someone trying to hit a personal target or KPI.
I also saw that the Sixers were advertising for a new Commercial GM a couple of months ago. Maybe that person is now in place and has just come in hot - pushing hard on delivering immediate results. So a similar thing, it's someone just trying to hit a current target and it's not financial trouble, just a new boss in the room with a new remit or a new approach that's different to the past.