I honestly think the market won't be reacting until the proposal goes through, if it does. It might be a good idea though to sell before the fork as exchanges get locked for days.
So if the price tanks during the fork, might be SOL.
If we "trial" this it will only set precedent that developers can code themselves more money and get away with it as long as it is a "shitcoin" like everyone else thinks we are.
The devs were the ones to propose it. Historically, miners rarely object to hard fork proposals due to how complicated it would make things, as well as fucking with market values.