>>780
招集ルールは基本的にアンダーかどうかで区別してない
"the representative teams of the country"と書いてあってすべてのカテゴリが対象
A代表だけ特別扱いの場合に限ってそのことを明記してる

第一項と第二項を読めばわかる
一応コピペしとく

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Annexe1: Release of players to association teams

1. Clubs are obliged to release their registered players to the representative teams of the country
for which the player is eligible to play on the basis of his nationality if they are called up by the association concerned.
Any agreement between a player and a club to the contrary is prohibited.

2. The release of players under the terms of paragraph 1 of this article is mandatory
for all international windows listed in the international match calendar (cf. paragraphs 3 and 4 below)
as well as for the final competitions of the FIFA World CupTM, the FIFA Confederations Cup
and the championships for “A” representative teams of the confederations, subject to the relevant association being a member of the organising confederation.