Injecting an upgradeable contract in another + deploying in parts

:1234: Code to reproduce

I’m using 2 upgradeable contracts: one ERC20 token and another which injects an IERC20Upgradeable value in its initialiser:

function initialize(IERC20Upgradeable _token) public initializer {

    _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
    _grantRole(PAUSER_ROLE, msg.sender);
    _grantRole(DISBURSER_ROLE, msg.sender);
    _grantRole(UPGRADER_ROLE, msg.sender);

    token = _token;

My current deploy.ts main():

  const BanzanToken = await ethers.getContractFactory("BanzanToken");
  const banzanToken = await upgrades.deployProxy(BanzanToken);
  await banzanToken.deployed();
  console.log(`BanzanToken deployed to: ${banzanToken.address}`);

  const RewardClaim = await ethers.getContractFactory("RewardClaim");
  const rewardClaim = await upgrades.deployProxy(RewardClaim, [banzanToken]);
  await rewardClaim.deployed();
  console.log(`BanzanToken deployed to: ${rewardClaim.address}`);

Is this the correct way or should I change it?

Also, if I wish to split the deployment, what’s the equivalent for <Contract>.attach for upgradeable contracts?
This would also be handy for testing.

:computer: Environment

Hardhat 2.8.3