Can a higher level review reverse a 100% P&T rating decision if I’m only contesting the effective date that my retroactive payment was initially made against?

I was awarded 100% P&T by the VA with an effective date of 3/31/22, but it seemed to be a clerical error since my effective date was actually 3/31/21.

I don’t believe it can be reversed at first glance when I’m only challenging the effective date on my claim, but if that’s not the case and it opens up everything again please let me know. Just trying to keep my family safe and provided for while I heal.

Thanks!