Using Timedata on Polisy to run programs at set minutes of the hour not working as expected

[cosyn]

I'm getting unexpected behavior from the ISY and Timedata node server.

I've had a greenhouse automation system set up through ISY for the past 5 years. I set up a Polisy earlier this year and am using a lot of the node servers with good success, eg, weather station integration, seasonal programs, etc. I'm trying to run a checking program that checks the humidity level (off an Insteon thermostat) at certain minutes of the hour (eg, at xx:00, xx:15, xx:30) and run a separate misting program that opens a valve (running off an EZIO) for a set amount of time if the humidity is below a set threshold. Here's the program:

The misting program is pretty simple. No conditions, open valve, wait, close valve. I have it set up this way due to reliability issues with the Insteon network and don't want the water to run endlessly.

Instead of running at the minutes specified, the system appears to be checking and running every few minutes. The log below shows it running every couple of minute when the humidity condition is met. I don't need it to run that frequently.

Any thoughts about why the ISY is not running the checking program at the minutes of the hour specified?

FYI, I have a Polisy running firmware version 2.2.10, Timedata 2.2.1, and ISY 5.0.16C. Thanks in advance.