Vias Under ESP32-P4

[Apostal2008]

Good afternoon,

The ESP32-P4-FUNCTION-EV-BOARD features vias located directly under the microcontroller.
I implemented a similar design, but I occasionally encounter issues where solder wicks into these vias from the central ground planes, causing signal lines to short to ground.

p4 vias.jpg (159.56 KiB) Viewed 497 times

How is this issue avoided during the production of the official dev board?

[Sprite]

It looks like the official devkit has solder mask over the edges of the ground plane (notice the fact that they're lighter colored than the center bit). If that's enough, I can also imagine it might use tented vias.