GEHA HDHP Employer Contributions

I just switched over to the GEHA HDHP this past open season. My understanding was that GEHA contributes $83.33 every month from Feb 2025 to Jan 2026 for this year, but on April 21st I have a random $80 employer contribution (in addition to the $83.33). Does anyone know what this is about? I don't want to accidentally over contribute because of this.