Usage of Schema Registry URL in Confluent Registry Avro Deserialization Schema (Flink)

I have a few doubts regarding the usage of Schema Registry URL in the ConfluentRegistryAvroDeserializationSchema.forGeneric(...) method in the flink-avro-confluent-registry package.

  1. What is the use of passing this as an argument? The way I understood it, its only used to set the writer schema and nothing else.
  2. If say I have a topic with 2 records r1 with schema s1 and r2 with schema s2 (s1 and s2 are slightly different - s2 has one new column than s1). Both schemas are registered in the schema registry. When I run a FlinkKafkaConsumer, and configure the deserialization schema as ConfluentRegistryAvroDeserializationSchema.forGeneric(s1, REGISTRY_URL), I see that the new column in r2 is completely ignored. I was under the impression that if the latest schema s2 is compatible with the record that was read, and that it would be used to deserialize the record. But now, that is not happening. What is the point of passing the URL?

Can someone please elaborate on this?