What are the risks of handling an ED visa for a 4-month internship in Thailand, and should my company assist with it?

And on that note we're done, Good luck to the O/P, TALK to your company about the internship and go from there.

My company has had many interns. Normally the school takes care of the visa and our company provides the supporting documents.

The maximum length of ed visa is 90 days, no matter the actual length of your educational program/even if it is a university issuing the letter of request to immigration. I’m here for PhD so After the 90 days, i extended my visa at immigration here (1900 baht).When I was doing an exchange program at university here for a semester ,I got the ed visa. After the 90 days, I just left Thailand to receive tourist visa because that gives me another 30 days to stay. It worked out well as I preferred to spend the money traveling than paying another extension/visa fee. But if you really want to get visa extension, perhaps you can ask if they can support that, give you the letter to immigration again.

you won't be able to get an extension on an ED visa based on interning in thailand 😮 It's just something not done (as in I have never ever seen it happen in many many years)

You get the ED visa, enter get stamped in for 90 days and when that's done, you either exit/re-enter on a free visa exempt entry (which is now 45 days) and which you can extend for 30 more days for 1900baht

OR

You go to a thai consulate and buy another single entry ED visa which will give you another 90 day stamp <- that is what I have seen people do who have a 6 month internship at companies