@jason123santa Yes, there is sadly a bandwidth limit for wireless transmission and the speed mostly depends on congestion.
A lot of the "increased speed" plans seems to be implemented via transmission priority I guess?

The limit is really airtime, rather than a set "amount of data" - if you're the only one in range of a tower, there would be no reason other than artificial ones for your tracking device to not to be able to use most of the airtime.