I frequently make calls to SW Support on behalf of customers and observe that the hold times are longer during the EMEA working hours than the US. If you call later in the day, there seems to be shorter hold times for support. If you call in the evening, the wait is even less, but you then have the coverage of the US sites and APAC.
This morning I had to wait only 5 minutes to call back regarding an outstanding case and the engineer handling my case answered. This is much lower than the average wait time and is welcomed on a Monday!
What would be really helpful for customers would be to have a call queue estimate, or call queue number, so you know how long you have to wait roughly and position number in the queue. If these were published on the customer portal, or on the support site, this would allow customers to decide whether to hold off calling until later, or raising a new case via the form Technical Support Ticket Submission Form | SolarWinds (I tend to use the forms where possible).
Garreth