So download window start/end time, by default it is set to 00:00 and 00:00 which means that download window is always open. Year is not important there.
Second screenshot, download window there is probably correct it will change every collection interval, so in your case every hour.
So, since your collection interval is set to 1h, your device will connect to the CMS every hour and download new/updated content schedule.
The most common issue with updating your content on the player is long running layouts (long durations) so you might want to check that.
as for
If there is nothing scheduled to display on the device (or the scheduled content is downloading or is invalid) then the device will display default layout, if the default layout is invalid (or updated with new content that needs to be downloaded first) then device will display splash screen.
That’s why we recommend some simple valid layout set as default one and more complex layout(s) scheduled.