You could check on the new requirements. There are some massive changes this year to the work visa programs. One such change is that you don't have to work in your field of education anymore.

Force inside a cylinder vessel is just pressure times surface area. If you have the same pressure(soda carbonation) with more surface area, then you are putting less force on the walls. I don't have any specialty in the materials engineering for canning, but i suppose less force on the walls means you could use thinner materials. However, soda can walls are already pretty thin to start with and from what I can find online, the tops are usually 2.5-3 times thicker. So, I could see it potentially cutting some cost from the tops by making them thinner but i doubt they are manufacturing different tops. It's probably just marketing.

You could try some bone conducting head phones. I've been wearing the Shokz brand OpenRun headband all day at work for about 5 months now and it's comfy. I use them in bed sometimes but don't fall asleep in them. They have some new wrap around ear ones that might be comfier to sleep in.

Edit: A full charge will last all day and they recharge quickly.

I used to be an Operations Manager at a machine shop with 150 employees and a Program Manager at another places with 250 employees. Both had 5am starts. In my experience, the biggest factor was support for the billable staff. You have direct labor employees; these are the people who run machines and fabricate products. Then there are indirect employees that support the direct employees; like purchasing, planning/scheduling, management, customer service, quality, etc. Most manufacturers with a 5am start time are running multiple shifts of direct labor. The indirect employees usually don't start until 7-8am and overlap both shifts to have some support for both day and night shift.

Manufacturers that run one shift(like my current job) usually start later. We start at 7am but allow people to flex their start time for kids, etc.