Bid and proposal submission instructions tell you how to send the offer: email to a contracting officer, a named portal, paper to a designated office, file-name rules, or a due date for the package. If FAR 52.215-1 is in the solicitation, proposals go to the office specified there by the time specified there. Commercial packages point to 52.212-1 and any addendum. Those rules apply before award.
Post-award invoicing and payment instructions tell a contractor how to bill after there is a contract. The payment system and the due date come from the awarded contract; they are not universal. Civilian agencies often use the Invoice Processing Platform, a Treasury Bureau of the Fiscal Service web service. Department of Defense contracts that include DFARS 252.232-7003 generally require electronic payment requests and receiving reports in Wide Area WorkFlow, accessed through the Procurement Integrated Enterprise Environment, with listed exceptions. FAR 32.904 generally makes an invoice payment due the later of the 30th day after the designated billing office receives a proper invoice or the 30th day after Government acceptance, except as prescribed for architect-engineer work, construction progress payments, food and specified items, and other listed cases. “Net 30” is not a universal term and is not a bid-submission method. In the uniform contract format those payment lines often sit in Section G, not in Section L.
AsherGate analysis keeps two labeled lists: Bid and proposal submission instructions, and Post-award invoicing and payment instructions. If a line about IPP or WAWF lands in the bid list, that is an extraction error to correct against the file. If the bid-submission list is empty, the product shows Not found in uploaded documents. That is not a reason to invent a portal, and it is not a reason to treat any AsherGate button as the destination.