How does "Concealment" transfer to Dedicated Transports?
The 10th Company's special rule Concealed Positions gives Stealth to each unit in the formation that deploys using the Infiltration rule.  We also know that the Dedicated Transport is a separate unit from the unit that disembarked. 


  Dedicated Transports do not use up any slots on a Force Organisation
  Chart, but otherwise function as separate units.


Therefore, if the transport moves, only the Dedicated Transport will lose Stealth. Each unit--independently--will have special rule Stealth until it performs an action that cancels it.