diff --git a/packages/types/src/primitive/Extrinsic/Extrinsic.ts b/packages/types/src/primitive/Extrinsic/Extrinsic.ts
index d884b6bcee..c57904a889 100644
--- a/packages/types/src/primitive/Extrinsic/Extrinsic.ts
+++ b/packages/types/src/primitive/Extrinsic/Extrinsic.ts
@@ -232,26 +232,7 @@ export default class Extrinsic extends Base<ExtrinsicVx | ExtrinsicUnknown> impl
   /**
    * @description Injects an already-generated signature into the extrinsic
    */
-  public addSignature (signer: Address | Uint8Array | string, signature: Uint8Array | string, ...args: [ExtrinsicPayloadValue | Uint8Array | string]): Extrinsic {
-    // FIXME Support for current extensions where 2 values are being passed in here, i.e.
-    //   addSignature(signer, signature, nonce, era);
-    // The above signature should be changed to the correct format in the next cycle, i.e.
-    //   payload: ExtrinsicPayloadValue | Uint8Array | string
-    let payload = args[0];
-
-    // FIXME The old support as detailed above... needs to be dropped
-    if ((args as any[]).length === 2) {
-      payload = {
-        blockHash: new Uint8Array(),
-        era: (args as any[])[1] as string,
-        genesisHash: new Uint8Array(),
-        method: this.method.toHex(),
-        nonce: args[0] as string,
-        specVersion: 0,
-        tip: 0
-      };
-    }
-
+  public addSignature (signer: Address | Uint8Array | string, signature: Uint8Array | string, payload: ExtrinsicPayloadValue | Uint8Array | string): Extrinsic {
     (this.raw as ExtrinsicVx).addSignature(signer, signature, payload);
 
     return this;