I honestly don't know and would be curious if anyone has already done this. I wouldn't be surprised if it still worked, at least to get you to the same planetary materials and ability kills step.
You're good as long as you didn't upgrade the other two swords on your alts.. You'll get the strike on Wednesday and then you can transfer the other two swords to your main.
Got it, thanks. Haven't touched the swords on my alts yet. So should I wait until Wednesday to transfer and upgrade?