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Abstract Coiled tubing (CT) lockup is where CT cannot progress any further into a wellbore. However, technical lockup occurs when less than 1% of the applied force can be transmitted through the CT. Industry leaders have developed a system where multiple extended-reach tools (ERT) are placed in a single string to overcome lockup in long laterals. This paper describes accurately determining the optimal up-hole ERT depth to overcome lockup and reach the desired depth. With the development of a multi-ERT solution and utilizing novel extended-reach modeling, real-time data can now be overlaid for operational and modeled data comparison. Through this comparison, it has been validated that technical lockup is realized at the up-hole ERT depth. However, the CT can still progress to plug back total depth (PBTD) since the string below (stinger) cannot be buckled and the on-end ERT alleviates its wall friction. Using this information, the stinger length can be technically derived from the modeled data and PBTD, providing confidence when designing these deployments. Although technical lockup is predicted in the multi-ERT model, operational lockup does not occur, as the CT progresses in-hole at a reasonable run-in-hole (RIH) speed. When the data is overlaid, notable friction increases are seen at the modeled lockup depth without an ERT and again at the modeled lockup depth with an on-end ERT. The second friction increase and set-down weight align with the predicted lockup weight, but the CT progresses to PBTD without any additional friction increases. This indicates that the string with two ERTs installed is acting not as one continuous string but as two distinct sections: the up-hole section above the ERT and a stinger below. This occurs as the weight being transmitted to the up-hole section can create buckling with the set-down force of the injector, but the weight transmitted to the stinger is below the helical buckling thresholds of the CT material. The on-end ERT no longer progresses the complete string into the wellbore but primarily removes the wall friction of the downhole section and applies weight-on-bit (WOB) to the plugs being milled. Utilizing a multi-ERT string design and the ability to model and monitor these CT strings in real time are new to the industry. Combining these new technologies allows the industry to continue to reach further in extended laterals while managing the previously misunderstood results due to downhole conditions. This solution is the next step-change required to continue reliably expanding CT reach as the unconventional market matures and demands longer horizontal operations.