Admiral Joy declared that the success of the Inchon assault depended on the employment of Marines trained in amphibious techniques; and he called upon Smith for his opinion. The Marine general said that a hastily instructed unit could not be expected to take the place of a combat-experienced regiment in the Landing Force, and that last-minute substitutions of this sort could not be made in complicated ship-to-shore landings without courting trouble. He added that it would be necessary in such an event to land in column on one beach instead of two, with the 1st Marines in advance of the 32d Infantry. These comments had the support of Doyle, who agreed that the availability of the 5th Marines might mean the difference between success and failure at Inchon. At this point Admiral Struble commented that the issue boiled down to the need for a mobile Eighth Army reserve. He suggested as a compromise that a regiment of the 7th Infantry Division be embarked and moved to Pusan as a floating reserve to be landed in an emergency as a substitute for the 5th Marines. This solution was accepted. Almond called up Eighth Army Headquarters immediately, and within an hour Wright telephoned to inform Smith that the Brigade would be relieved at midnight on 5 September.[98] [98] O. P. Smith, _Notes_, 74–80. _Chronicle_, 31 Aug-3 Sep 50; Forney _Special Rpt_, II, 4. As it turned out, the 17th Infantry of the 7th Infantry Division was embarked and transferred to Pusan to substitute for the 5th Marines, with Marine officers of Training Team Able assisting in the outloading. After the amphibious assault, the regiment landed administratively at Inchon to rejoin its parent unit. _Naval Gunfire and Rockets_ At a conference on 1 September called by Admiral Struble and attended by Admirals Richard W. Ruble, John M. Higgins, and Sir William G. Andrewes (RN)[99] in addition to Generals Ruffner and Smith, it was tentatively agreed that the cruisers would begin the bombardment on the morning of D-minus 1, and the destroyers that afternoon after a napalm air strike had been conducted against Wolmi-do on D-minus 4. [99] See Appendix E for Naval Task Organization giving components, ships, and commanders of JTF-7. At another naval gunfire conference two days later, the napalm strike was delayed until D-minus 3. On 8 September, when Admiral Struble held his final meeting, PhibGru One and the 1st Marine Division agreed on the scope and timing of naval gunfire support. It was decided, therefore, that the bombardment would commence on D-minus 2 and be repeated if necessary on D-minus 1.[100] [100] O. P. Smith, _Notes_, 72–74.