The over-pressure heat-treatment (OPHT) processed Bi-2212 insert coil technology for high field (>24 T) magnet applications greatly depends on two critical techniques developed at the Applied Superconductivity Center at National High Magnetic Field Laboratory (ASC/NHMFL). The optimized OPHT process makes Bi-2212 multi-filament wires obtain high in-field critical current density (JE ~900 A/mm2 at 20 T) with its good uniformity along the wire length ranging to typical wire production lengths of 1.3 km. Another critical technique developed at the ASC/NHMFL is a versatile stress management scheme for the Bi-2212 coils using alumina-based fiber to endure high magnetic stress caused by Lorentz forces during operation. In 2022, we were able to operate a test coil withstanding over 350 MPa of JBr stress while producing a magnetic field of 4.9 T in 12 T background field. Confirming the potential of Bi-2212 coil technology for further development, we started “long” Bi-2212 test coil development in 2023 as a steppingstone towards a full-size Bi-2212/LTS magnet system providing Φ 54 mm and > 20 T for internal research users. One of the main objectives of these new developments is to make an up to three times longer test coil than we made in 2022, so that we can confirm effectiveness of the stress management technique against axial thermal shrinkage during cool-down and axial magnetic compression during operation for the full-scale Bi-2212 coils. While the first mid-scale coil showed an unexpected low performance last year, another mid-scale coil has been wound and will be tested in 2024, to evaluate the current Bi-2212 coil technology from the perspective of their in-field performance, stress management and mechanical integrity, magnetic field uniformity, field temporal stability, and Bi-2212 coil protection.