I do appreciate you sincere interest.

Businesses and people could always do any (legal) thing with their money, including investments of all kinds at any time. All people or businesses could make last-minute purchases, including investments, to keep from losing that money, but in the process might be putting some other person or business over the limit they were allowed to retain. For businesses, a lag of a quarter before any overage had to be remitted to the administrator of the money (central bank of Monetary Agency) would smooth things out.

Like many people, you seem to have a hard time keeping government out of it. Government would have nothing to do with creating or distributing the money. It would merely be the recipient of money in the same way individuals would be.

The administrator of the supply of currency (central bank or monetary Agency) could not run out of money because it would simply be creating money as needed to fund the allotted income and government. The less that came back to it, the more it would have to create, is all. (If imports exceeded exports, that would be another reason it might have to create more money.)