Of course the WA DOL site is a web app that doesn't support deep linking. You can get to the web app to check plate availability and rules here: https://fortress.wa.gov/dol/extdriveses/NoLogon?Link=Persona...

You may have to visit https://www.dol.wa.gov/vehicleregistration/sppersonalized.ht... first.

When that photo was published, WA was still running sequential plates as three digits followed by three letters; since then, they ran out, and they chose three letters followed by four letters. When that runs out, they will most likely switch to four numbers followed by three letters, so it makes sense to reject personalized plates that match the future series of sequential plates.