田中さんの言うとおり、土地の管理はA社の担当ですので、この契約案を(事前にB社の了解を得たうえで)A社に確認してもらって締結作業を進めるという方向で良いと思います。
添付でお送りしている契約案は、W契約で定められている土地(すでに無効になっている土地も含む)については一切言及せず、現在かつ未来に有効な土地を「追加」する(「修正」ではない)こととしております。従来の契約で得た権益を失わないためにこのような文言の変更を行っています。これについて何らかのリスクがありますでしょうか?
As Mr./Ms. Tanaka says, it is company A's responsibility to take care of the land, so it will be okay to get approval for the contract draft from company B in advance, get company A to check the draft, and go through with the conclusion.
The contract draft that I have attached does not mention anything about the land that has been governed by the double contract (including the land that have already been invalid), and states that at present or in the future, the valid land will be "added" and not "revised." The prose have been revised so that the profits and rights earned from past contracts would not be lost. Does this have any risks involved?