Button for New Record With URL Redirect

So, I have this problem that just started happening on Thursday.  We have a few tab pages that contain a URL redirect button to create a new record for that tab’s object. When the user clicks on the button, they get redirected to the create new record page. It has always worked prior to Thursday without a problem.  Now, when they click on the new record button, they get redirected to the standard Salesforce login page even though they’re already authenticated. We have a custom domain and SSO enabled with MS Azure that syncs with our on-prem active directory. When they usually see the login page, Salesforce automatically redirects them to our sign-on page for Azure. However, now they see the standard login screen and it’s confusing them because they have to know our custom domain in order to login. 

I've checked my config on the SSO and it seems to be on the up and up. The initial login process redirects to Azure and recognizes the custom domain as it should. The only thing that I can think of is the URL in my button. Has something changed with the URL's that I missed? The URL just takes them to the SKUID page for creating a new record in that object

The URL I’m using is- 

Hi Colby

Does it help, when you change it to a relative url? 

Like: /apex/UI?core.apexpages.devmode.url=1&retURL=%2Fa0F%2Fo&sfdc.override=1&objecttype=Purchase_Order__c&actiontype=New

Of course that works. I’m not sure why I didn’t think of that. Thanks!