Historian Motoki KURODA questions the date on account of Akisada YAMAUCHI-UESUGI's letter, in which it is written that the Yamauchi-Uesugi clan attacked a stronghold thought to be Odawara-jo Castle in 1496, and listed among the forces with the Ogigayatsu-Uesugi were Fujiyori OMORI and Soun's younger brother Yajiro ISE; therefore, Soun's capture of Odawara-jo Castle must have occurred thereafter.
黒田基樹は明応5年（1496年）に山内上杉氏が小田原城と思われる要害を攻撃し、扇谷上杉方の守備側の名に大森藤頼と早雲の弟伊勢弥次郎の名が山内上杉顕定の書状にあったことを根拠に年次に疑問を呈し、それ以降のことではないかとしている。