As Champ Labs alone previously (before ff) provided all AZ STP blue can filters it's true that some were "ecores" using the nylon/plastic cage. Others however were Champ classic metal endcap construction with a separate bypass. The S6607, and S2808 were examples of Champ classic construction. The 3614 has been an ecore using a combo valve. The old Super Tech filter line was very similar, but ST offered a classic construction 7317 application too.
One change in STP blue can supplied by 'fram filtration' fram/champ made filters is the S2808 now Fram fiber endcap construction. The S6607 still classic construction, the 3614 still an ecore. The ff made STP made filters still sold in AZ's locally, and the topic filter S10590 is an ecore.
Seems the information provided that all AZ STP blue cans had been 'off shored' and those ff made left old stock, was inaccurate. I found the topic S10590 with a manufacture date first week this month.