message: backed out the block wait, issue was actually _not_ a race condition
diff: @@ -22,7 +22,7 @@ import {
  getSendPayload,
  executeSend,
  } from '../utils/safe-utils';
  -import { waitUntilBlock, waitUntilTransactionMined } from '../utils/general-utils';
  +import { waitUntilTransactionMined } from '../utils/general-utils';
  import { signSafeTxAsRSV, Signature, signSafeTxAsBytes } from '../utils/signing-utils';
  import { PrepaidCardSafe } from '../safes';
  @@ -487,10 +487,7 @@ export default class PrepaidCard {
  createPrepaidCardTxnHash: string,
  onTxnHash?: (txnHash: string) => void
  ): Promise<void> {
  - let receipt = await waitUntilTransactionMined(this.layer2Web3, createPrepaidCardTxnHash);
  - // wait 2 block confirmations to ensure blocks have propagated to relay server
  - await waitUntilBlock(this.layer2Web3, receipt.blockNumber + 2);
  -
  + await waitUntilTransactionMined(this.layer2Web3, createPrepaidCardTxnHash);
  let relayServiceURL = await getConstant('relayServiceURL', this.layer2Web3);
  let url = `${relayServiceURL}/v1/prepaid-card/${prepaidCardAddress}/load-gas/`;
  let options = {
  