When a solicitation you’ve reviewed changes, identify which posting governs, classify the change (metadata, Q&A, revised attachment, or formal amendment), compare six things against your previous read, log every difference against the matrix row it affects, reassign owners, check the acknowledgment instruction, and reopen the pursuit decision if a disqualifying or unresolved row moved. Keep the earlier version. A change log that overwrites the past can’t show a reviewer what you knew when you decided.
This checklist covers changes before award. Post-award modifications belong in contract obligations.
The before/after amendment exercise uses a retained base RFQ and Amendment 0001. Read the source panels, record your answer, then compare it with the worked decision and handoff. Company decisions in the exercise are fictional.
Four kinds of change
Not every new posting is an amendment, and the difference decides what you owe.
| What you observed | What it is | What it obliges |
|---|---|---|
| A new “updated” date on the notice, a new contact, a corrected NAICS | Notice metadata | Record it. Check whether anything in the attachment changed. Usually nothing to acknowledge. |
| Questions and answers added to the notice text or an attachment | Buyer clarification | Read each answer against the matrix. An answer can change a row’s interpretation without changing the solicitation text. |
| A replaced attachment, drawing list or CDRL | Revised document | Diff the old and new file. Record the change and its locator. |
| A numbered amendment (SF 30 or equivalent) | Formal amendment | Compare every section it names, update the rows, and acknowledge it the way the solicitation instructs. |
For negotiated procurements, FAR 15.206(a) says that when “the Government changes its requirements or terms and conditions, the contracting officer shall amend the solicitation”, and 15.206(g) lists what each amendment should contain at a minimum: the solicitation number and date, the amendment number and date, the number of pages, “description of the change being made”, and “revision to solicitation closing date, if applicable.” That list is your comparison template. Commercial-item and sealed-bid procedures have their own rules, so read the instructions in the solicitation you’re holding.
The six comparisons
- Scope. Line items, quantities, specifications, deliverables.
- Access. Technical data conditions, custodian instructions, delivery system.
- Status and timing. Which certification or status, at which checkpoint. A Q&A answer often moves this one.
- Submission instructions. Format, address, contents of the offer, acknowledgment method.
- Evaluation. Basis of award, first article conditions, waivers.
- Dates. Response date, question deadline, site visit, and the amendment’s own issue date.
Do the comparison against your locator map rather than from memory. A change you can’t locate in the old version is a change you can’t prove.
The change log
| Change ID | Before (document, locator) | After (document, locator) | Old text | New text | Affected matrix rows | Checkpoint | Owner | Action and due | Acknowledged | Decision impact | Reviewed on |
|---|---|---|---|---|---|---|---|---|---|---|---|
Decision impact takes one of three values: none, revisit, or reopen. Reopen means a disqualifying or unresolved row changed and the pursuit decision goes back to whoever made it.
A worked example, with its gap
The DLA Aviation RFP for an F-16 20mm transfer unit housing (SPRWA1-26-R-0017) was posted on SAM.gov on 4 August 2026 with a response date of 10 August. On 24 August 2026 a new posting in the same family opened with: “This notice is being updated to provide additional questions/answers as received by the USG and to issue the attached RFP Amendment 01.” The posted response date on that notice was 25 September 2026.
Here’s the log as far as the retained notice text supports it.
| Change ID | Before | After | What changed | Affected rows | Decision impact |
|---|---|---|---|---|---|
| C-1 | Notice of 4 Aug, no subcontractor Q&A | Notice of 24 Aug, Q&A 1 | New answer: CMMC requirements flow down to subcontractors that will handle FCI or CUI, citing DFARS 252.204-7021(d) and 32 CFR 170.23 | Flowdown row (new), award checkpoint | Revisit if any subcontractor will touch CUI |
| C-2 | No first article waiver answer | Q&A 2 and 3 | First article test may be waived for offerors that supplied the same or similar article to the Air Force within 36 months, per Form 260 Block 11 para c. Applicable CDRLs removed on waiver | First article row, submission checkpoint | Revisit. Possible cost and schedule change |
| C-3 | Response date 10 Aug 2026 | Response date 25 Sep 2026 | Posted response date changed | Dates row | None on eligibility. Changes the plan |
| C-4 | No amendment | ”attached RFP Amendment 01” | Formal amendment issued | Unknown until the amendment is read | Reopen pending |
C-4 is the row to watch. The notice text says an amendment was attached. Our retained copy holds only the notice text, so the log records that a formal amendment exists and that its contents are unreviewed. That row stays open until someone downloads Amendment 01 from the SAM.gov record and diffs it. A log that guessed at the contents would be worse than one that says “not yet read.”
Two more cautions from this family. The 10 August date on the earlier posting reads as the closing date for the interest stage, so C-3 is recorded as “posted response date changed” rather than “deadline extended.” And the earlier posting’s CMMC clarification called the requirement “CMMC 2.0 Level 2 - (Advanced)” while the later one says “CMMC Level 2.” Different words, same row, worth a question.
Acknowledgment
Read the solicitation’s own instruction. For negotiated acquisitions, FAR 52.215-1(b) says offerors “shall acknowledge receipt of any amendment to this solicitation by the date and time specified in the amendment(s).” For commercial acquisitions, FAR 52.212-1(b)(9) lists “Acknowledgment of Solicitation Amendments” among the contents of an offer, and a DLA Land Warren package we reviewed carried a fill-in block on page 2: “Acknowledge all the amendments received from the Contracting Office by identifying the amendment number and its issue date below.” An unacknowledged amendment can make an otherwise complete offer incomplete. The deadline and acknowledgment guide covers the mechanics in more detail.
Where Deep Fathom fits
Your team compares versions, records the changes and assigns follow-up work. Where a changed requirement creates compliance or evidence work, Deep Fathom supports evidence management and obligation-to-work traceability. Keep the original package and change log in your team’s controlled records. This guide does not promise automatic amendment detection or version comparison by the platform.
The contracting officer issues the amendment. Your team retains the source versions and decides whether the pursuit stands.
If a changed requirement touches a security or evidence row, send our team the amendment number and the new response date. Our team will show which compliance and evidence workflow applies to the changed requirement. Review bid requirements
Related reading
The retained jack-assemblies amendment case supplies a verified base/amendment pair. Read why a pursuit decision has a version date for its management implications.