Ever since a few versions ago - I have been unable to upload an application build to testflight.
Here is the log - complete with debug:
Started by user anonymous
[EnvInject] - Loading node environment variables.
Building remotely on macmini-05 in workspace /Users/Shared/JenkinsSlave/Home/workspace/UScapeit-iOS
Uploading to testflight
File: Engineering/iOS/UScapeIt/UScapeIt.app.ipa
DSYM: Engineering/iOS/UScapeIt/UScapeIt.app.dSYM.zip
POST Request: testflight.TestflightUploader$UploadRequest@8d5f3bf[filePath=Engineering/iOS/UScapeIt/UScapeIt.app.ipa,dsymPath=Engineering/iOS/UScapeIt/UScapeIt.app.dSYM.zip,apiToken=*******,teamToken=*******,notifyTeam=true,buildNotes=This is the latest build of UScapeit (for iOS) which was built by Jenkins UScapeit-TestFlight 3.0.126.49
,file=Engineering/iOS/UScapeIt/UScapeIt.app.ipa,dsymFile=Engineering/iOS/UScapeIt/UScapeIt.app.dSYM.zip,lists=UScapeIt,replace=false,proxyHost=,proxyUser=,proxyPass=********,proxyPort=0,debug=true]
java.io.FileNotFoundException: Engineering/iOS/UScapeIt/UScapeIt.app.ipa (No such file or directory)
java.io.FileNotFoundException: Engineering/iOS/UScapeIt/UScapeIt.app.ipa (No such file or directory)

Here is a log from the machine - proving to me that the files actually exist:
bash-3.2$ hostname
macmini-05.mok3.com
bash-3.2$ pwd
/Users/Shared/JenkinsSlave/Home/workspace/UScapeit-iOS
bash-3.2$ ls Engineering/iOS/UScapeIt/UScapeIt.app.*
Engineering/iOS/UScapeIt/UScapeIt.app.dSYM.zip
Engineering/iOS/UScapeIt/UScapeIt.app.ipa