If Joe Biden is elected president of the US in 2020, will the highest tax bracket be restored to its original 39.6% or higher before 2025?

In the Tax Cuts and Jobs Act of 2017, Republicans and President Trump advocated for lower taxes and reduced the highest tax bracket from 39.6% to 37% effective the 2018 tax year.

If Joe Biden is elected president of the US in 2020, will the highest tax bracket be restored to its original 39.6% or higher before 2025?

[fine-print] This question resolves:

• Positive if Biden is elected president for the 2021-2024 term, and the upper tax bracket for US single tax payers is increased to at least 39.6%.
• Negative if he is elected but the upper tax bracket is not increased to at least 39.6%.
• Ambiguous if he is not elected President in 2020. [/fine-print]