The answer to this question can be found at 16.703(d)(2) which states Contracting officers shall....(iii) If applicable, cite the authority under 6.302 in each order; and (iv) Comply with 5.203 when synopsis is required by 5.201. FAR Part 5.001 Publicizing Contract Actions is applicable to contract actions as defined in Subpart 2.1, which includes "job orders or task letters issued under basic ordering agreements; letter contracts; orders, such as purchase orders, under which the contract becomes effective by written acceptance or performance." Both 16.702(c) Basic Agreements and 16.703(c) Basic Ordering Agreements state the agreement shall not "state or imply any agreement by the Government to place future contracts or orders with the contractor; or be used in any manner to restrict competition".
FAR 1.602 (b) states "No contract shall be entered into unless the contracting officer ensures that all requirements of law, executive orders, regulations, and all other applicable procedures, including clearances and approvals, have been met." Neither a basic agreement nor a basic ordering agreement are contracts. They are simply an agreement of terms and conditions between a contractor and the Government to be incorporated into a order (contract) should the Government determine through competitive procedures that issuing the order is the best contractual mechanism to obtain the specific goods or services. This is why you are writing a justification and approval document in accordance with FAR Part 6.302 for each order issued under the BOA. Reference FAR 16.703 (d)(1) Before issuing an order under a basic ordering agreement, the contracting officer shall -- (i) Obtain competition in accordance with Part 6; (ii) If the order is being placed after competition, ensure that use of the basic ordering agreement is not prejudicial to other offerors; and (iii) Sign or obtain any applicable justifications and approvals, and any determination and findings, and comply with other requirements in accordance with 1.602-1(b), as if the order were a contract awarded independently of a basic ordering agreement.
Depending on which Part 6.302 authority you are citing for justifying using other than full and open competition procedures would determine if a pre- and/or post- synopsis was required when issuing an order under the BOA. For example, if you are citing 6.302-1 (10 USC 2304(c)(1)) "Only One Responsible Source and No Other Supplies or Services Will Satisfy Agency Requirements", you would need to follow the synopsis procedures in 6.302-1(d)(2) Limitations, which states (1) Contracts awarded using this authority shall be supported by the written justifications and approvals described in 6.303 and 6.304; (2) For contracts awarded using this authority, the notices required by 5.201 shall have been published and any bids, proposals, quotations, or capability statements must have been considered.
If you are citing 6.302-2 (10 USC 2304(c)(2)) Unusual and Compelling Urgency, you would need to follow the procedures in 6.302-2(c) Limitations, (1) Contracts awarded using this authority shall be supported by the written justifications and approvals described in 6.303 and 6.304. These justifications may be made and approved after contract award when preparation and approval prior to award would unreasonably delay the acquisition (2) This statutory authority requires that agencies shall request offers from as many potential sources as is practicable under the circumstances; and the synopsis exception at 5.202 (a)(2) which states "The proposed contract action is made under the conditions described in 6.302-2 (or, for purchases conducted using simplified acquisition procedures, if unusual and compelling urgency precludes