Not really. Apps that are signed with a free account expire after 7 days, which makes the free side loading pretty much useless. With a paid account, they work indefinitely.
Maybe not, I haven't tried that yet. But yeah "indefinitely" was probably not the right word. It might very well depend on some certificate with some expiration date. But it's very manageable.
https://www.google.com/amp/s/9to5mac.com/2016/03/27/how-to-c...