A few variables and the timeline for the shortage to ease:
1) The pandemic slowed down production of copper and manufacturing. The pandemic impacted quite a few things in the production cycle.
The timeline to solve that depends on how effective President-Elect Biden's pandemic plan is. He has declared it his #1 priority.
2) The social unrest caused a surge in demand. With Trump now ousted, that situation will get much better. He has been agitating that problem for the last four years. We should see a return to normal now that the instigator is gone and people have no reason to be vocal against the government. Sorry, I don't support the current government and respect the anti-government protestors. Just like the Boston Tea Party, they are telling the government they do not approve of 4 years of inflammatory abuse.
3) Like the toilet paper hoarding, people obtain more than they will need. At some point the hoarding is maxed. Let's all be honest, there are not going to be any shootouts anytime soon, and people are loaded up on ammo that will never be needed.
4) The Senate is Republican, Biden is a well-know compromise moderate, and there is not going to be radical gun control legislation. We are going to get restored background checks and perhaps enhanced. The rest of it has zero chance.
5) Now that the election is over, which is uncertainty driving fear, the bad government causing all these problems gone, and then people see bad does not happen. Summer will be the return of normalcy.
July 2021 is the answer now that the election is over.
The bad government is gone and with it these problems it caused.
The new government is restrained by the Conservative Supreme Court, Republican Senate, and the preference to be a moderate compromiser by the new president.
July 2021.