My nexus 5 doesn't support Sprint Spark, which uses LTE band 41 but it works with LTE band 26. The speed is about 40mbps. Meanwhile, my nexus 6 speed is about 75mbps with Sprint Spark.
Really what a joke, I've been hearing that for nearly 3 months now, just like the KitKat update for my wife's G2, first quarter is over very soon, but I know its coming soon...so is Christmas
PRL updates may actually happen more frequently than realized. They serve to keep the device updated with regards to contacting the towers of other carriers while not on the Sprint network. Unfortunately, we do not get much, if any, advanced notice as to when device updates will be pushed. You can, however, keep an eye on www.Sprint.com/Newsroom as it may be announced there once a date or date range is set.
Sprint Social Care Team
I'm aware, I was just noting that just because you get a PRL update, doesn't mean Sprint Spark is coming in the next day or so. That's what I was trying to refer to.