Print area issue

Since you've been using this same document/template for years, it sounds like the printer defaults are what has changed. But start here...

When you're in Print Preview, below the preview, does it indicate you are looking at Page 1 of 2? With Page 2 being the 2nd half of your tabled document? Since your paper measurements are roughly twice as wide as tall, it looks like the print job is selecting Portrait mode for you.

Print Settings - first does the print setting indicate Landscape mode? And 1 page per sheet? Assuming these settings are correct, go to 

Printer Properties - Is the Printer pulling directions from the document file Print Settings? Landscape, 1 page per sheet?

 If everything is looking like it should (landscape, 1 page per sheet), try refreshing the printer/Word connection. Switch to a different printer (I suggest Microsoft Print to PDF). Does it still show a bad preview? If it looks right now, switch back to your original printer. Did that fix it?

If not, try opening and printing other landscaped documents. If they are behaving badly also, it's possible that an auto-update to the printer driver didn't go well. If you are the only user on the printer, you might try 1) turning it off and back on again (yes, really), 2) removing/reinstalling the printer. If this is a networked printer controlled by the IT guy, tell them they broke it or another user changed settings on the printer.