No it really is not an issue, an estimate is non posting and does nothing to the accounts
when you create an invoice from an estimate, the estimate closes, and the invoice when saved is a final sale.
so the transaction is complete
QB has a tag that could be used, but the implementation is screwy
a job, sub customer, the job title will be moved to a field called project on the invoice
BUT the project field is only visible on a print or print preview
open invoice, click the formatting tab, click customize data layout, on the header tab find the field and check mark it for print, you can try checking it for on screen - maybe something changed