It's 6-8pm on a Wednesday night for me. That's terribly inconvenient here in NZ too!
Unfortunately, you'd probably find that more than 90% of Spark's users are American. Therefore they ARE going to operate at a convenience to the American users, as that's their site majority.
I just make a mental note not to bother trying to Spark on Wednesday evenings. Perhaps you'll also have to just skip Wednesday mornings on Spark and look forward to Thursday morning when you can then catch up on everything you need to do.