Android All Firebase Libraries Must Be Above or Below 14

It seems like the condition (Must Be Above or Below 14) apply to both Firebase and Play services.

dependencies {
    // def playServiceVersion = '15.0.1'
    implementation 'com.google.android.gms:play-services-plus:15.0.1' // + playServiceVersion
    implementation 'com.google.android.gms:play-services-location:15.0.1' // + playServiceVersion
    implementation 'com.google.android.gms:play-services-places:15.0.1' // + playServiceVersion
    implementation 'com.google.android.gms:play-services-auth:15.0.1' // + playServiceVersion

    // def firebaseVersion = '15.0.0'
    implementation 'com.google.firebase:firebase-invites:15.0.1' // + firebaseVersion
    implementation 'com.google.firebase:firebase-core:15.0.2' // + firebaseVersion
    implementation 'com.crashlytics.sdk.android:crashlytics:2.9.5'}

Latest libraries version: https://developers.google.com/android/guides/releases

Check latest play-services-* version: https://mvnrepository.com/artifact/com.google.android.gms/play-services-location

Check Latest firebase-* version: https://mvnrepository.com/artifact/com.google.firebase/firebase-core

NOTE: Since version 15, all Play services and Firebase libraries is no longer required to have the same version number in order to work correctly at build time and at run time - Source