Pretty sure Google Earth has undergone some updating in just the last few days, but resolution has not be affected as far as I can tell. One thing that has changed is that the "historical image data" - that used to automatically show up as a slider bar at the lower left, now has to be accessed by clicking an icon tab at the top. This has changed in just past 4 days. I've also noticed that the time it takes for the image to reach its best resolution is longer in past few days, but I just figured that was my internet connection, but it could be Google updating things as well. I've run into this in the past, as I've used GE for work and play for 8+ years now.
The IMAGERY DATE, not copyright date, is always shown at the lower right corner -- although you have to zoom to a certain level to get it to show up.
Most importantly, un-check any features in the SIDE BAR that you don't really need or have to use. Things like borders and labels, photos, 3D buildings, terrain, etc. This will improve the image quality. Especially make sure "terrain" is turned off as this does affect image quality. If you don't have the sidebar automatically showing up, click the icon (first one on the left) at the top to make it show, and be sure to un-check anything you don't need. The only thing I have checked is "roads". With Google updates, these settings can change, so it may be helpful to review those settings.
My version is Google Earth Pro, and I've had it so long I don't know if there is another version out there or not. Still free however.
Linda