Originally Posted by
UAL250
Definitely Tue/Wed. There's plenty of PZ space (for us lowly platinums and below :P) out of IAD and ORD (and even SFO and EWR on some routes) for most flights to Europe on those two days.
I rarely see any PZ space in advance, whatever day of the week. PN space is possible if you are willing to take literally any route from the West Coast to Europe - ti shows up about once a week, but nowadays PZ available weeks or months in advance is not happening (summer season apart).