Configuration Variable for defaul plot config file

We use custom plot configuration files for each project to adjust output colors of fill shapes and utilities for our plan sets. These are stored in the symb folder in our project directory. The problem is every time a new dgn is added to the pset, it resets the plot config to "FDOT.pdf".

Is there a default project configuration variable that would make this select my project plot config when adding new DGNs instead of reverting to FDOT.pltcfg?

I checked this master list here: but none of the ones I tried seemed to work.

Thank you!