Paid from old incorrect claim

Apologies ahead of time for formatting as I'm using my cell. Hopefully this isn't too confusing...

I lost my job in early March right before everything hit the fan. I filed my claim and after some delay, as it was adjudicated, I was approved.

The year before (2019) my ex-employer had screwed up some paperwork and I was without a license to do my job. I was out of work for about a month so I didn't use all my benefits I was approved for at the time.

Fast forward to around October and my claim from 2020 ran out and it automatically reverted to my claim from 2019 that pays much less. At the time I didn't think much of it as I know they're overwhelmed and figured things would work themselves out. I'm also a disabled vet so I'm used to the hurry up and wait along with the bureaucracy. So I just let it be.

Anyhow, come the end of January I finally called. I explained that I didn't think I should be getting paid from my claim from 2019 and should have had my claim from 20 extended. After being placed on hold a few times to consult with a manager she said that I was correct and should be using the 20 claim. Furthermore, she said that there isn't anything they can do until the claim runs out (something about system updates) but when it does I'll be eligible for back pay.

My questions are:

a. Is she correct in that I should be getting paid from my 2020 claim and not my 2019?

b. Does that make me eligible for back pay?

c. Is it correct that they cannot make any changes to the claim and I have to wait for it to run dry?

d. Is there anything I can do to correct this now or, at the very least, ensure that if I still have to claim come time the 2019 claim runs out it gets paid out correctly?

Hope that's not too confusing...

Thank you for any and all help or advice!!

TLDR: 2020 claim ran out, it automatically reverted to 2019 claim that pays less. I was told there's nothing they can do until it runs out again. What should I do?