Watch firmware v1.5.25 was released today, 25 Mar 2015. Or at least that’s when it installed on my AMBIT3 SPORT. Presumably the same /similar firmware is also available for the other AMBIT3 variants.
I’m yet to look in more detail but this could be the anticipated March update listed <here>.
Today I did a multi-paced interval run looking at the accuracy of the AMBIT3 vs. 920XT with respect to the CURRENT PACE. Interesting results that I’ll post up soon.