I also think people fear the “only one offer” policy at DFARS 215.371 when soliciting for less than 30 days.
(a) If only one offer is received when competitive procedures were used and the solicitation allowed fewer than 30 days for receipt of proposals, the contracting officer shall—
(1) Consult with the requiring activity as to whether the requirements document should be revised in order to promote more competition (see FAR 6.502(b) and 11.002); and
(2) Resolicit, allowing an additional period of at least 30 days for receipt of proposals; and
but they miss the exceptions for acquisitions under the SAT & small business set-asides:
(a) The requirements at sections 215.371-2 do not apply to—
(1) Acquisitions at or below the simplified acquisition threshold;
(2) Acquisitions, as determined by the head of the contracting activity, in support of contingency or humanitarian or peacekeeping operations; to facilitate defense against or recovery from cyber, nuclear, biological, chemical, or radiological attack; to facilitate the provision of international disaster assistance; or to support response to an emergency or major disaster;
(3) Small business set-asides under FAR subpart 19.5, set asides offered and accepted into the 8(a) Program under FAR subpart 19.8, or set-asides under the HUBZone Program (see FAR 19.1305©), the Service-Disabled Veteran-Owned Small Business Procurement Program (see FAR 19.1405©), or the Women-Owned Small Business Program (see FAR 19.1505(d));
(4) Acquisitions of science and technology, as specified in 235.016(a); or
(5) Acquisitions of architect-engineer services (see FAR 36.601-2).