T-Mobile L41 Band

In my travels today, I went into NJ towards Vincentville (around 130 and 206).  Band 41 (4G/LTE) is showing up a lot.  It seems like the sites South of my area (Levittown, PA) are being converted to T-Mobile.  I'm assuming T-Mobile is going from South to North.

The screenshot below shows the band 41 coverage from my travels today.

Here is confirmation of the new band 41 sites (Cellmapper).  In July, the sites on the New Jersey side were showing up but over the last week or so, L41 is starting to show up more near me.