Basically once my MacPro wakes up, the Wi-Fi icon is greyed out and it takes like a minute (which feels pretty long), before it connects to my home Wi-Fi network.
This happened already a few times over the last year. It starts happening without a good reason, and it fixes itself also like that. Utterly annoying.
I cleaned up my Wi-Fi list (only 3 networks in it) and my home network is on the top.