If there is a certain invoice/bill that you would like to exclude from the cash flow forecast you can do this from the main cash flow or the 'Invoices Due' and 'Bills to Pay' sections.
In the main cash flow click into the relevant cash flow cell to generate the budget popover. On the top of the popover click into the 'Due' section which will display all the invoices/bills that impact that cell.
Clicking into the invoice will show the invoice popover and in the top right you will see an 'Include in cash flow' option that shows ticked when included.
Simply move the toggle to off, save the change and the invoice will be excluded from the cash flow.
The action of excluding an invoice/bill can also be carried out in bulk from 'Invoices Due' and 'Bills to Pay'. Just select the invoices you want and go to Batch Actions > Exclude.
It's easy to locate excluded invoices/bills in the 'Invoices Due' and 'Bills to Pay' sections as these will display an excluded tag.
Any excluded invoices/bills can be re-added from the 'Invoices Due' and 'Bills to Pay' section at any point by switching the toggle back on.
If multiple invoices/bills need to be included or excluded these can be updated in bulk.