CO2 neutrality does not make sense in the context of a timeline. it is a mathematical rate, positive being an increase in the atmospheric reservoir and negative being a decrease in the atmospheric reservoir.
No amount of time producing "nearly neutral" increases to the atmospheric reservoir will produce an improvement in runaway existing CO2 feedback loops.
A mathematical rate literally includes a timeline. Common timelines for rates are per second, per hour, and per year. Saying “CO2 neutral per two years” is non-standard but valid.
No amount of time producing "nearly neutral" increases to the atmospheric reservoir will produce an improvement in runaway existing CO2 feedback loops.