Adding Billable Time to an Existing Invoice

Is it possible to add billable time to an existing invoice? The invoice is generated at the beginning of the month and is a work in progress for project work. As work is done the invoice would get updated accordingly. The billable time procedure allows us to create a new invoice (as per guide) which in most cases is great but not what we wish to achieve. So how can we charge out a project extending over the month in increments as employees add their time to the project? I do not want to create the project invoice from chargeable time on the last day of the month (too much checking to be done). I find changing the status of the billable time and assigning to the “project’s invoice” results in no entry of that time and description in the assigned "project invoice. Is there a solution to this?

Now I have tried this dating thing above by changing the Invoice date to the beginning of the month and all Billable Time following the Invoice Date on the 1st of the month and vice versa where the Invoice date is at the end of the month and all billing dates during the month before the invoice date. The results give / show the same outcome … No billable time in the assigned Project Invoice.
Using Server Version: Manager 17.1.39

All your lengthy explanation aside, you currently can’t add billable time (or expenses) to an existing sales invoice. The program just wasn’t designed that way.

Billable time is meant to “remember” what you’ve worked on so you can bill client for it at the end of period. If you want to create invoice and then keep adding billable time to it, why do you need Billable Time tab at all? Just edit the invoice and add new line item which would be categorized to “Consulting income” account or similar.

I get the point. At first I thought it was a bug when the billing time did not show up in the said invoice. I guess it is more of a management thing when it comes to multiple people entering their time and then allocating it to an invoice only to find that it does not manifest itself in that particular invoice. The key thing for us is that we do not want the engineers to finalize or enter directly into the invoices (no need for staff to know the value of a particular project / invoice). The account manager would follow through with finalising the invoices. So on the face of it, it appears that this task of invoice generation from billable time will need to occur at the end of our billing cycle. OK as you point out…

It would be a “nice to have” from our perspective as far as the business flow goes and integration of billable time with invoicing.