The gist of what happened, based on what I can glean from the IDW forum thread:
- IDW have been selling their Transformers comics online via Comixology to customers in Continental Europe for several months now.
- Apparently they never actually had the license to distribute their comics there, but their storefront was too half-assed to actually block people from buying based on their location.
- Someone (probably Hasbro) caught on to the fact that, hey, IDW can't actually do this.
- IDW summarily stop selling comics to those territories, but don't communicate anything to their customers.
- Since no one bothered to tell them that they couldn't legally purchase the comics anymore, fans all across Europe were effectively shut out from buying several weeks worth of comics.
- Some fans (it seems to vary based on region and the app used to purchase) are reporting that they can no longer even access the comics they've already bought and paid for.
Crap like this is why so many people still illegally download comics. A content provider deciding that they won't sell to you and that you can no longer use the stuff you've already bought is a worst-case scenario for digital media consumers, and the fact that IDW made absolutely zero attempt to warn their customers before cutting them off just makes the whole thing ten times worse.