Win 10 Pro

Win 10 Pro 1809.17763.195
This past week I started receiving a message pop up from MS that my login in password is about to expire. This morning when logging on my PC, another message reminder that my password will expire in 3 days. I have never experienced this this before, should I be concerned?
Will I be locked out if I don't change my Local User and Admin passwords?

As a first step can you check what it shows under "Password never expires" in Local Users and Groups as shown in Option One Step 5 as displayed in this tutorial ?

Enable or Disable Password Expiration for Local Accounts in Windows 10 | Tutorials

If the Option "Password Never Expires" is already checked and you still got the message reminder, maybe someone more knowledgeable may be able to help.

@das10 Thanks for your help!
I never thought of checking the Local Security Polices as nothing had been changed. However, following your suggestion, I checked the LSC and indeed it had been changed (local user acct.) to MS default of 42 days. There must have been a glitch with an update. Going back in history I did get a CU (39 days back) KB4467708 11/22/208.

Glad to hear you got it sorted.