I received the following email from Google Cloud about changes to Cloud Functions for Firebase:

Since Cloud Functions for Firebase is built on Google Cloud Functions, we’re writing to let you know about some changes that are being made to the Google Cloud Functions.

What you need to know

Starting September 1, 2024, future versions of the gcloud functions deploy CLI command will create Cloud Functions using 2nd generation by default. If you do not wish to create a 2nd generation function, you can override this behavior by using the --no-gen2 CLI flag.

Additionally, the firebase-functions Node.js SDK will begin defaulting to the v2 API instead of the v1 API. The v2 API is available now at firebase-functions/v2.

Cloud Functions for Firebase has two product versions:

Cloud Functions (1st generation), the original version, used whenever targeting the firebase-functions/v1 SDK.
Cloud Functions (2nd generation), a new version built on Cloud Run and Eventarc providing an enhanced feature set, which has been generally available since 2022.
This is used whenever you need to target the firebase-functions/v2 SDK.

You can learn more about the benefits of Cloud Functions for Firebase (2nd generation) in the Cloud Functions version comparison documentation.

What you need to do

If you are unable to upgrade at this time, change your import from firebase-functions to firebase-functions/v1 to preserve your existing codebase.

If you automate the creation of new Cloud Functions for Firebase evaluate the differences between generations when creating 2nd generation functions to avoid any issues.

If you conclude that you need to create functions in 1st generation, update your imports from firebase-functions to firebase-functions/v1 before September 1, 2024.

We’re here to help

We know this change may take some planning, and we're committed to supporting you during this transition. If you have any questions or require assistance, please contact Google Cloud support.

I currently don't have a plan to upgrade to firebase-functions v2 and want to upgrade functions one by one while keeping the existing v1 functions in our PRD environment.

My questions are:

1, If I don’t redeploy my existing functions after September 1, 2024, will they be affected in any way?
2, Is it mandatory to update imports from import * from “firebase-functions”; to import * from “firebase-functions/v1”; even if I don’t redeploy those functions?
I am concerned that if I change the imports, I might need to test the entire app, including functions that are not redeployed.
Any insights on these questions would be greatly appreciated.