Storage life of Palladium 3?

Does anyone know how long a 15% solution (in distilled water) of Palladium 3 (Sodium chloroplatinate, and I know Bostick and Sullivan call it chloroplatinite) will last? This has use both for Palladium printing and as a component in some toners for salted paper. I know mixed salted paper toners incorporating Pd3 have a limited life, I’m asking here about what would be considered a “stock solution”.

For extra credit, how about some of the other precious-metal stock solutions associated with Platinum and Palladium printing?

I also intend to ask the good people at Bostick and Sullivan.

Thank you.

So far, with storage times going from months to years (I started pt/pd printing in ~1998), I have not noticed any issues using the two common pt and pd salts, nor with Na2.