When account is upgraded, will embed code change at all?

If a free account is upgraded to a paid account (and the Jotform branding is removed), will the embed codes change at all?

No, you don't need to recreate the embed code, the branding bar will be automatically deleted.

The only exception is if you embed your form via Source Code option. In the source code option, the branding bar is embedded in the generated source code. So you need to recreate the source code.

If you have any other questions, feel free to ask.