Unable to scale up more than 7 replicas

[rakeshk121]

The mongo-k8-sidecar works fine for replicas upto 7 but when it is scaled up beyond 7, the new members are unable to join the replica. As per my analysis the issue is due to a constraint that mongo allows only 7 members as voting members even though there can be max of 50 members in the replica set. The sidecar configures all the members as voting members, so scale-up beyond 7 is not working fine. Is there any configuration that i can do to fix this?
Here is the error log of the sidecar of PRIMARY replica:-

Error in workloop { MongoError: Replica set configuration contains 8 voting members, but must be at least 1 and no more than 7
    at Function.MongoError.create (/opt/cvallance/mongo-k8s-sidecar/node_modules/mongodb-core/lib/error.js:31:11)
    at /opt/cvallance/mongo-k8s-sidecar/node_modules/mongodb-core/lib/connection/pool.js:497:72
    at authenticateStragglers (/opt/cvallance/mongo-k8s-sidecar/node_modules/mongodb-core/lib/connection/pool.js:443:16)
    at Connection.messageHandler (/opt/cvallance/mongo-k8s-sidecar/node_modules/mongodb-core/lib/connection/pool.js:477:5)
    at Socket.<anonymous> (/opt/cvallance/mongo-k8s-sidecar/node_modules/mongodb-core/lib/connection/connection.js:333:22)
    at Socket.emit (events.js:182:13)
    at addChunk (_stream_readable.js:287:12)
    at readableAddChunk (_stream_readable.js:268:11)
    at Socket.Readable.push (_stream_readable.js:223:10)
    at TCP.onStreamRead [as onread] (internal/stream_base_commons.js:122:17)
  name: 'MongoError',
  message:
   'Replica set configuration contains 8 voting members, but must be at least 1 and no more than 7',
  operationTime:
   Timestamp { _bsontype: 'Timestamp', low_: 1, high_: 1591844848 },
  ok: 0,
  errmsg:
   'Replica set configuration contains 8 voting members, but must be at least 1 and no more than 7',
  code: 103,
  codeName: 'NewReplicaSetConfigurationIncompatible',

[rakeshk121]

Scalling the mongo-stateful set beyond 3 as well does not seem to work. The current mongodb replica can be scalled up to 3 replicas(due to mongo-sidecar limitation) and scalling beyond 3 will fail to re-elect the members of the replica upon pod non-graceful restart of the pod and the system reboot