Hi RedDuke, I think that account can double maybe not for 1 month but for 2 month (about 40 trading days) I think that can double - if we talk about Binary option. (But you need be really expert, i am not, I am avaerage trader and will try if lose in the end it not big money which I lose. I will get more trading expirience anyway.
It's another thing if we're talking about forex then probably must be a lot more time.
Broker is Olymp Trade (primarily binary option broker but can also trade forex with them) but be VERY CARFULLY if you want deposit and trade on them because they have only this regulation
https://financialcommission.org/olymp-trade/ but they not regulate through CySEC or FCA etc...
My expirience with them in total is good don't have any problem (deposit, withdraws was very fast (not large deposit and withdraw), also support is very very fast from my experience)