October 1 might seem like a silly time to ask for more money. Lots of company’s do year end performance appraisals and year end raises, so it seems a bit early.
Budgets are made in advance.
If your company does a year end raises, the budgets for those are made now–or may already be made. You don’t have any say over how much money is available, and unless you report directly into the CEO, your boss probably doesn’t have much say about the available cash. Your boss will get a budget (probably). That budget is probably arriving soon.