I can answer all your questions about Billable Time, @HMDieselRepairs. But I dont’ want to bore you with stuff you’ve already seen. Have you read this Guide?
But to answer your most obvious question:
Yes, absolutely, for anything that went out on a sales invoice. Otherwise, that sales invoice will never be paid. And any time that was temporarily being recognized under Billable time - invoiced will remain there forever.
@Brucanna is right about using Expense Claims when you buy things for the company with your personal funds. Make sure you’ve read: