If your project is urgent, maybe you can get a temporary solution through http://ai2-test.appinventor.mit.edu, but it should be noted that there is no guarantee that the built app can run stably on android 12 currently.
Robert, a developer can do this however he/she still needs to wait for the arrival of nb190 later this month. Your suggestion can be used to test the creation of the aab however it is NOT SUITABLE for submission to Google Play yet. 
Just to clarify a few things since there appears to be a bit of confusion in this thread.
- AAB build support is available in production App Inventor, and has been for a while now.
- Only new apps need to target SDK 31 at this time. Existing apps that are updated have until Nov 1, 2022 so this does not affect any previously published apps.
- As mentioned, we do have a test version at ai2-test that targets SDK 31 as part of our summer upgrade. It's important to manage your keystores properly if you plan to use that server in the interim because it is a completely separate system from ai2. While we believe this system is mostly stable it is a beta version and may not meet your needs.
3 Likes
Hello
I do all the steps that @Anke tell me and
I update in the manifest to target 31 and i convert to aab file then I sign it with the mit app inventor keystore
When I publish to google play this message show to me
You uploaded an APK or Android App Bundle which has an activity, activity alias, service or broadcast receiver with intent filter, but without the 'android:exported' property set. This file can't be installed on Android 12 or higher
I think this is a second problem
I hope you solve the problem because ai2 is very important for me
Import your project (aia) to http://ai2-test.appinventor.mit.edu/ and build the APK and check the Manifest (compare it with your edited Manifest).
You can also try to create the AAB (on the test server) and upload it to Google Play (developer console) as an internal test track and wait for the Pre-launch report.
2 Likes
Note:
If your app is a new app (and only in this case you must target SDK 31), you do not need to import the keystore from AI2. You can use the new keystore that the test server generates for you.
1 Like
Ok thank you yes it's a new application
@Anke Soy nuevo en esto es mi primera app que creo. Pero la verdad no entiendo nada de lo que escribiste. Podrias ser tan amable de aplicarme como edito o abro el manifiesto. Para poder seguir sus instrucciones. Cuando saldria la actualización de la que hablan.
How can do it? Plz send sreenshot
I m facing same problem, google play gave error due to api level 31. I cant upload my .aab file. What is the solutions? Thanks,
Did you read the solutions provided in the topic ?
3 Likes
Yes i read and i generated new .aab file from test page, took this message
The Android App Bundle is signed with the wrong key. Make sure your App Bundle is signed with the correct signing key and try again. Your App Bundle is expected to be signed with the certificate with the following fingerprint:
SHA1: 85:AA:C2:08:25:82:EF:FC:CE:DB:9F:20:C4:00:FE:A3:30:C2:0E:98
. The certificate used to sign the App Bundle you have installed has the following fingerprint:
SHA1: 94:5F:D6:41:7F:E8:70:40:A3:B7:40:18:E4:30:6C:FC:31:BD:EB:9D
Then it is not a new app that was uploaded to the Google Play Developer console for the first time.
1 Like
how to set target sdk version 31?
Please read the topic!!
I created this app on 09th August. 
how to decompile apk and set target api 31?
That was / is not the question, but was this app uploaded to the Google Play Developer console for the first time? Apparently that is not the case.
Yes, last thursday I tried to upload but I didnt able to do it, then today morning I generated new .aab file as per mentioned before message, I am taking same error message unfortunatly.