Spring Boot 2.4.0 / spring-cloud-starter-vault-config 3.0.0-M6 not resolving server

Cloud Config is also going through Eureka and that one is working. Just Vault isn't. Both are set up the same way in bootstrap. App worked fine in SB 2.3.6 / SC 2.2.6.

bootstrap:

# specify the active profile

spring.profiles.active=Dev

# Eureka client bootstrap settings

eureka.client.service-url.defaultZone=https://xxx:yyy@eureka01.xxx.com:8761/eureka/
eureka.client.register-with-eureka=false

# disable Ribbon load balancer

spring.cloud.loadbalancer.ribbon.enabled=false

# Config client bootstrap settings

spring.cloud.config.discovery.enabled=true
spring.cloud.config.discovery.serviceId=xxx-CONFIG
spring.cloud.config.username=xxx
spring.cloud.config.password=xxx

# Vault client bootstrap settings

spring.cloud.vault.discovery.enabled=true
spring.cloud.vault.discovery.service-id=xxx-VAULT
spring.cloud.vault.token=xxx
spring.cloud.vault.generic.backend=kv
spring.cloud.vault.generic.application-name=xxx

build.gradle:

buildscript {
    ext {
        springBootVersion = '2.4.0'
        springCloudVersion = '3.0.0-M6'
        reactiveFeignVersion = '2.0.25'
    }
}

plugins {
    id "org.springframework.boot" version "${springBootVersion}"
    id "io.spring.dependency-management" version "1.0.10.RELEASE"
    id "java"
    id "org.sonarqube" version "3.0"
    id "com.github.ben-manes.versions" version "0.36.0"
}

group = 'org.xxx'
version = '0.0.1-SNAPSHOT'
description = 'xxx-Test'

sourceCompatibility = '11'
targetCompatibility = '11'

repositories {
    mavenCentral()
    maven { url "https://repo.spring.io/milestone" }
}

dependencies {
    implementation "org.springframework.boot:spring-boot-starter-web:${springBootVersion}"
    implementation "org.springframework.boot:spring-boot-starter-security:${springBootVersion}"
    implementation "org.springframework.boot:spring-boot-starter-webflux:${springBootVersion}"
    implementation "org.springframework.security:spring-security-oauth2-client:5.4.2"
    implementation "com.google.guava:guava:30.0-jre"
    implementation "org.springframework.cloud:spring-cloud-starter-bootstrap:${springCloudVersion}"
    implementation "org.springframework.cloud:spring-cloud-starter-netflix-eureka-client:${springCloudVersion}"
    implementation "org.springframework.cloud:spring-cloud-starter-config:${springCloudVersion}"
    implementation "org.springframework.cloud:spring-cloud-starter-vault-config:${springCloudVersion}"
    implementation "com.github.ben-manes.caffeine:caffeine:2.8.6"
    implementation "org.apache.commons:commons-text:1.9"
}

spring-cloud / spring-cloud-vault

Spring Boot 2.4.0 / spring-cloud-starter-vault-config 3.0.0-M6 not resolving server #550