setUserAgent not Working on Private Instance(Safari and IE 11)

Hey,

I am noticing a problem with my private instance where I try to set the user agent it does not work on Safari or IE 11, rather it remains the same default agent. Setting the user agent on Firefox works fine via the script and using the uastring arg to set the useragent on chrome works as well.

I am on the IE11/Chrome/Firefox/Safari (2014, wptdriver only) - ami-561cb13e test agent.

The user agent I am trying to set for these are
Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.152 Safari/537.36 WebpageTest

I am using the api to pass in the script. so here is how the script is sent in.

"logData 0\nsetUserAgent " + uastring + "\nlogData 1\n navigate " + url

Where uastring is the string mentioned above and url is some url.

I notice that the user agent is set when on http but the site redirects to https which fails to set the user agent. I tried to run a test with the https url and the user agent is not even set in this case.