No list was made on 11-22-63. The list on 24H260 was the list created on 11-26-63. And yes, it's been altered. The DPD sent two shells over on 11-26-63, and one later. Someone--it's not clear who--then changed the inventory list to reflect that three shells were sent over. Perhaps they knew there had been three and had assumed the two was a mistake.
In any event, if the goal had been to fool someone, they failed. The WC sent the FBI out to talk to Fritz Sims and Day and filed numerous reports explaining how it came to be that only two of the three shells were sent to Washington on the 22nd and 26th.