Supporter pack upgrades and steam

Now that the game is out on Steam and we can purchase points and packs through Steam. Is it possible that you could make it so we can upgrade packs through steam too, like we can through the website?

A side question, is it only possible to buy up to the 120 dollar pack on steam? It seems so and I guess its because of limitations on the steam wallet and market system, but just want to make sure.

Michael@GGG mentioned in this thread that points purchases made through Steam since release count toward supporter packs, up to the second tier ($120). So if you already bought points over the past month, and probably even if you do so now, you can at least get the $120 pack that way.

(I may have misread that slightly. I think for upgrades you may need to contact GGG's support if it involves Steam payments.)

I just went ahead and used my preexisting point purchase through website from before steam launch to upgrade from. The point purchases on steam are smaller than it anyway. Still would be nice if Steam upgrades were possible.

Points I bought in-game through Steam, don't show up on my past transactions.