IIS: module cannot change application pool of existing iis application

Basic Info
Module Version: 4.2.0
Puppet Version: 4.10.8
OS Name/Version: Windows Server 20125

Desired Behavior:
When an existing iis application has a different application pool from the one in the puppet configuration then a puppet run should change the iis application application pool to the correct one.

Actual Behavior:
Puppet will not change the application pool of an existing iis_application regardless of whether the current settings match up to those in the manifest.

Example scenario:
Setup:

• Root website "mySite" exists and running on it's own app pool "mySite"
• No iis applications exists
• 2 app pools setup: "wrongPool" and "rightPool"
• Using the attached manifest (example.pp)

First puppet apply (see attachment: 1-app-doesnt-exist.log):
myApp is created correctly and has the application pool "rightPool" as expected.

Second puppet apply (see attachment: 2-app-correct-pool.log):
myApp is not changed and still has the correct application pool "rightPool"

Manually change myApp's application pool to "wrongPool"

Third puppet apply (see attachment: 3-app-wrong-pool.log):
myApp is not changed and still has the wrong application pool "wrongPool"

Notes: the log files have been cleaned up a bit to remove company details