Testing non PRV nights - error with completing download and system hang

[maswain]

HI,
As part of testing hiresprv, I tried some non HIRES prv nights:
2016-10-05
2016-10-06
2016-10-07
2015-06-06

After the system downloads the first night, the system remains in a busy state.

When I try to cancel the active job, I get a JSON decode error (see attached)