RSC permission ChannelMessage.Read.Group is not working for GetTeamChannelsAsync method

Hi Team,

We are using a chatbot for a live agent conversation. So we have team groups with multiple team members as agents.

Currently, we are using the Manifest version 1.11 and used the below permission to send message without @botname 

"webApplicationInfo": {
		"id": "<bot app ID",
		"resource": "https://AnyString",
		"applicationPermissions": [
			"ChannelMessage.Read.Group"
		]
	}

This change we have done last year and it was working till last week without any application permissions or admin consent. We were able to send message without @mention and also able to get channel data with the GetTeamChannelsAsync method which is part of the Teams bot APIs 

Since yesterday we have been getting forbidden exceptions while accessing the agent details. Because in code we are using 'TeamsInfo.GetTeamChannelsAsync' for validating the agent.

In teams app we are seeing new area 'required permissions' under permission tab

Does this change has any other issues with using GetTeamChannelsAsync  for getting channel data. Do we need to add extra permission in app registration to get the channel details. But it was working till last week with RSC permission in manifest file.