RE: Example: Bill dated 6/22/24, no payment made yet (no customer:job). This transaction shows up as a COGS expense (again not connected to any customer invoice) on the P&L for the period 6/17/24 to 6/23/24. It should not be here as no payment was made during that period.

This will happen in some cases if you purchase an inventory item on the Bill and the item has previously been oversold. If your purchase is for a different price, compared to the estimated COGS used when the invoice was oversold on a sale, then the adjustment will appear as a result of the later purchase on Bill.

There may be other causes as well. Not sure.

RE: Example: Invoice date 6/17/24, Payment date 6/1/24. This transaction shows up as revenue on the cash basis P&L for the period 6/17/24 to 6/23/24. It should not be here as there was no payment received during that period.

This is normal. It happens when there is a prepayment because, though you have the cash, you have not yet earned it until the invoice date - the date you make the sale - the date that there is an actual business transaction.

Also, to recognize the income on the payment date in this case would set up a case where you might never see the income. Consider a payment received near the end of your financial year that remains unapplied to anything far into the following year, when you finally record and complete the sale. It would not appear on your P&L for the year of receipt as it isn't applied to anything, and as a result there's now way to know what it's for. And then later when it was applied, it would also not appear on that year's P&L because the payment was last year.

For this reason, cash received is not considered income until it is earned. For example, a deposit on account to secure an item you may someday obtain and then sell to the customer is not income until you complete the sale. Instead it is more like a loan - and in the case that you someday make a sale, it can be applied to that sale. But if you aren't able to make the sale, then you'll give the money back.

Note that, even on a cash basis not all cash received is income and not all cash paid is an expense. As examples, cash received from customers for sales tax is not income, and cash paid to purchase inventory is not an expense.