@josh mark yeah that's almost certainly thermal bleed from the GNSS module — multi-constellation tracking with an 18Hz fix rate keeps that thing working hard, and on a dense carrier board the heat doesn't have anywhere to go except into whatever's sitting next to it.
The fix that actually works is physical separation — even 15-20mm of PCB trace gap between the two modules makes a real difference, and if you can route a slot or a thin air gap in the board between them that's even better. If your layout is locked and you can't move them, a software offset calibration will get you close but you'll need to account for the fact that the offset won't be constant — it'll shift depending on how long the GNSS has been running and how many constellations it's actively tracking.
Worth checking what fix mode you're running too — if you don't need the full 18Hz rate for your application, dropping the update rate reduces the processing load and the heat output noticeably.
