Warren Pottery ashtray pitcher apprentice signed red clay

I have 2 pieces of pottery that are signed Warren.  One piece is signed  "apprentice" with Warren and another name on the bottom.  Any information would be appreciated.

The clay and the style looks somewhat like the Hastings pottery of Dennis Lucas, which in various entities ran from 1956 to 1995. They concentrated on small items for the Gift trade, and their work was ubiquitous in Boot Fairs some years ago. This looks looks like gift trade ware. Their production was fairly significant, so they probably employed a number of potters. If it is not Hastings, then it is from a similar type of pottery.
However, if 'Warren' is a Christian name, then your chances of finding out exactly who he was are probably fairly remote, as apprentices did come and go in this type of pottery, with no records as who they were,

As you’re based in the US it’s very unlikely it’s by Hastings Pottery which is a U.K. pottery. I’m afraid I don’t recognise the name, and the first signature looks like it’s stamped on a molded base. The signatures are so similar I wonder if they are a company stamp rather than studio ware.

I found another one online with "S.A." in a circle incised under the Warren"