This paper focuses on pilot and controller issues linked to alternatives for absorbing delay in metering conditions under four-dimensional trajectory-based operations (4D TBO). We specifically explored combining two robust and complex tools, Required Time of Arrival (RTA) and three-dimensional Path Arrival Management (3D PAM) Efficient Descent Advisor (EDA) to yield more accurate and reliable delivery to the meter fix while maintaining operational efficiency. This represents the first time that these two robust and complex tools, one airborne (RTA) and one ground-based (EDA) have been used together. The data demonstrated that the combination of RTA (for speed) and EDA (for path) offered significant capacity for absorbing delay, and these two tools seemed to work well together. Specifically, the speed management of RTA was sufficiently stable and accurate to preserve 3D PAM conflict detection and avoidance and active conflict probe functionality. Potential safety and operational impacts/mitigations and human factors issues requiring further exploration are presented.