Backdated SF50 Tenure Group change?

I have been a fed since 2018, and completed two probationary periods (2018-2020 DOD, 2021-2022 VA) and have been in my current job series since 2021.

I was hired to my current position under the 30% or Greater Disabled Vet Preference in December 2023. December 2024 an SF50 was processed with an effective date of my date of hire, acknowledging no probationary period, converting to permanent, and acknowledging tenure group 1.

Yesterday I received an OPF email that I had multiple documents added, with effective dates going back to the hire date of my current position.

All of these were to change previous SF50s since I started in this position to Tenure Group 0. The earliest was approved 02/25/2025, changing my tenure effective my hire date (12/31/2023) and removing the earlier remark that I had completed service requirements for career tenure from 04/30/2018 to 04/30/2021.

I have every expectation that my office will be hit by RIFs, so losing tenure is kind of a big deal.

I'm not seeing why I would have lost tenure. I know 30%+ preference is a temporary appointment, but I was converted to permanent status (and this was an existing FTE slot) previously.

Does anyone have any insight before I go raising a stink?