Zanetti, in general, the system allocates accounts to the nearest most suitable server cluster. Not only due to bandwidth and other such technical things but also in regards to their time zone.
When an account gets placed in a server, it's going to stay on the server for good. So when some users travel the world due to holidays and/or their work, and it's right before the beginning of the season (when fixtures are being drawn), it can happen that these managers will give the system a bit of a hard time when registering comfortable match times for everyone in each competition group.

We're really sorry that this happens from time to time, and know it's uncomfortable in some cases, but due to technical limitations we currently can't make the situation better. It just happens sometimes. I hope you understand. :/

Btw, just so you know - I'm an old player here in Top 11 so I've also have had to play at some ridiculous hours every now and then and do know how uncomfortable it can be.