Hi There,
Two things come to mind - this could be the gpo “slow link detection” kicking in and not applying GPO because it believes that the client is on a slow link.
Second, if you manage to get onto an affected device, run gpresult /h c:\temp\result.html
The result might yield why policies are not getting applied.
You might need to change the directory of the output if you have writing to the C drive locked down, maybe write it to the users home drive?
Marc