Backup team lead

Soooo what do y'all think of this title? Is it bs? Doing all the work of a TL, but not the same pay? Or is it a step for moving up to actual TL? What if you're promised TL after being backup TL for a while?

Adding this- A coworker was backup team lead for about a year. We both just interviewed for actual TL. They were given the position. I was asked if I would want to assume the role of backup team lead and told there would be a spot opening up very soon for another TL. But no actual date of how soon. I was told had the other person not applied, I would have 100% gotten TL. So far, I've been learning new things. Which is nice. I've not been asked to stay late or come in early. I have been told to tell other people what to do. I have been asked to cover the new TLs lunch, break. So far, I don't really find it much more work. My coworkers don't seem to hate me and seem to do the tasks I ask happily and willingly. I think that because the new TL was formerly a backup TL and now actual TL that hopefully there's hope for me as well. We're very much move up from within our own department versus bringing in people from other stores.