Your English must be much better than mine because I did not spot any grammatical errors, let alone typos... Can you please enlighten me as to where such errors are?
Without accepting your premise that my English is better than yours, below are the issues I had with the e-mail, in the order they occurred. Some are minor, stylistic things, and some are more significant. I'll list them all, with explanations.
"In short, it is taking much longer than expected and we plan on installing the seats in your car by the end of May at the latest, although hopefully earlier than this. "
hopefully is not used correctly. It should have been written something like "although we hope it will be earlier than this." (This was a really minor issue. I wouldn't have criticized the e-mail message if this had been the only issue.)
"We were overwhelmed by the high demand for P85D in general, and specifically for the next gen seats."
I think this should read "for the P85D" or "for P85Ds" or something else. Again, this is not one of the larger issues.
"The lead times from many of our suppliers have doubled due to the port situation and that have prevented us from both giving you an accurate lead time to change, and allowing us to start building your new seat."
OK, here we go. For starters it definitely needs to be "that has prevented us..." not "that have prevented us..." And what does "giving you an accurate lead time to change" mean? Also in this sentence, no one is getting just one seat. Everyone is getting either two front seats, or three back seats, or both. The last word in the sentence should be "seats."
"We now have line of sight and we are planning to have built and replaced your seat by end of May at the latest (unless we have a complete shutdown of the ports which remains, unfortunately, a possibility)."
Line of sight? That's not a common term the way it's being used, and while I guess the intended meaning can be figured out from the context, it's a poor choice of words. The second "we" in that sentence is unnecessary and awkward. Built and replaced is also an awkward way to say that. The seat can't be replaced without being built first. And again, seat should be seats. Also it should be "by the end of May..." not "by end of May..." The period in that sentence should be inside the close parentheses symbol.
I would never critique a personal e-mail from Jerome this way. But Jerome has a staff. An e-mail like this one had to have staff involved. I could be wrong, but I believe English is not Jerome's first language. (I would never be able to tell that from reading any of the e-mail messages I've received from him personally.) So I don't fault Jerome for this at all. Before this e-mail was sent, someone from the communications department should have taken a look at it and edited it. And if someone from the communications department was not available to do it, then someone on Jerome's staff should have. I'll state again that I have to believe this was some sort of mistake that slipped out without being proofread. I don't recall seeing any other communications with these kinds of errors from Tesla.