we are currently very concerned by the M365 Message Center announcement "MC696169 Legacy SharePoint Invitation Manager is being retired". We do not allow standard users to invite B2B guests in our Entra ID directory. Therefore, if a standard user shares a document from SharePoint Online with a "new guest", the external person can authenticate with a One Time Passcode (OTP) via email. We are using this process quite intensely. The message center announcement says that the legacy feature was only used when a whole library was shared externally. However we were suspicious and created a MS support case. The engineer says, that the whole OTP process without guest account cannot be used any longer when the change has been implemented. Sharing documentes from within SPO will always trigger the invitation of a guest account. This is a desaster for us, as all OTP links that have been created so far will become unusable. SPO tries to invite the account as guest in the context of the account that shared the document, which fails due to the "no invitation for standard users" policy. On top of that the change has been communicated December 7th and the rollout will start in January, so we do not have any time to prepare.
Are there any other companies facing issues with this change? If yes, have you taken any action towards Microsoft? I requested a postponement of the change but that was not successful.
