I passed my general written test 3 months ago, but failed the Morse Code
test. Will I be able to automatically upgrade to General once the rules change
or do I need to take a new general written Test?

As I understand it, neither. You'll need to go back to a VE session,
bring your CSCE (the certificate which documents the fact that you
passed the written exam), pay another exam fee (probably), and have
them submit the paperwork for your General. The CSCE remains valid
for one year after the date on which you passed the exam.

So, it's not automatic, but you won't actually have to retake the exam.

--
Dave Platt AE6EO
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