How long can a aircard charge in its cradle

We have an Aircard 810S that we use as a hotspot and we were thinking of buying an AirCard Smart Cradle to hold it.  Can a cradle with an attached Aircard be left on indefinitely? 

Our existing Aircard is currently used almost exclusively in a shared use room and we leave it on charge all the time.  It however turns itself off after charging for a while. As the room is used by multiple people we would prefer not to require people to turn it off and on all the time. We like the flexibility of being able to disconnect the AirCard and use it elsewhere as there are some times we need to take it out of the office and we would prefer not to pay for two data plans.

Thanks in advance.