Chosen Solution
I have just replaced a badly broken screen. I was very careful to remove LCD and store with care while iPad was sent for a soldier repair. The LCD now shows white with large vertical black lines. Faulty LCD?l
Sure sounds like a faulty LCD but you won’t know until you test it. I would test another LCD and if that doesn’t fix it, it could be related to the board repair you had done. What was the board issue?