Nope, there's a difference. You have a P2715Q monitor. The P-series is a 'cheap' series, whereas the U-series is the Ultrasharp monitors. The Ultrasharps are calibrated to outstanding color values (the blacks: not so much, and the lighting uniformity could be better), but they are very good in color. The P-series, as far as I know, are not from the same quality. In addition, the U-series feature the 4-sided borderless design, while the P-series still have the thicker 'chin'.
Then the numbering: the 27 stands for the size. So you have a 27" monitor, while
@adamjackson has a 32" monitor.
The 15 in your monitor stands for the model year: 2015. The 3419 is 4 years newer than the 2715. I'm not sure what the Q stands for, but it has to do with the specs. For instance, the monitor i have, is available without usb-c (U2719D) and with usb-c (U2719DC).
So no, it is not a slightly updated version of your monitor, it is a different line of monitors and it is 4 years newer than yours.