not sure if it was mentioned but odds staking is going away from what i heard..... new update for duel arena is going to auto convert ur stats to 99 while in duel arena so there will be only max main staking
from the osrs update page
Real World Trading through the Duel Arena
The Duel Arena is an iconic part of Old School RuneScape, yet it has its problems. The Duel Arena is currently fuelling Real World Traders that stake based on odds to acquire huge sums of in-game gold, which they then sell online. We do not want to remove the Duel Arena from the game as it's particularly iconic to the feel of Old School RuneScape. So we'd like to discuss some options with you in order to address the problems we face:
An option to adjust your stats, similar to the Tournament Worlds. This option would mean that the odds stakers lose their advantage, and we keep the Duel Arena open.
A trade weighting limit on stakes which would prevent one side being heavily weighted over the other. This again is with the intention of stopping odds stakers. It would work akin to the trade limit of old. You can stake as much as you'd like, but your opponent has to stake an amount which is within a certain range of your stake.