Can you have more than one project Lead

[Terry]

Given that any one person assigned as a project lad maybe unavailable for a long period of time, or leaves the company, can you assign multiple Project leads as backups

[Jack Brickey]

No but you could give another user the necessary permissions to accomplish many tasks. What exactly do you want this secondary person to be able to do?

[Terry]

Archive old projects

[Jack Brickey]

So are you on premium subscription? That is required to perform project archiving. Assuming that you are to the best of my knowledge there is no permission scheme for project archiving it simply falls under being a project or Jira admin.