Just throwing this out as an idea to start the conversation off. You could accomplish this using the schedule manager in console to do a check of tickets that qualify for a notification to be sent. IN hindsight of typing this up it's probably better to use a value other than the word NULL, I don't know if LANDESK code may interpret that value as a system command somewhere, so using No or NoNotification might be a better choice than NULL.
1) In object designer create a "placeholder field" to hold a value for your specific field above.
2) That calculation may look something like this and be a Before Save calculation
static def GetAttributeValue(Request):
** The dependency on the calculation would be your specific field above, in window manager you would have to go in and set that field to is calculated for this to work.
3) Each time this field has a change it's going to copy the value in to your placeholder field.
4) Create a new Action in process designer. This action is going to set the value above back to NULL when the scheduler from step 7 is run. For the option Allow Association with Window, set to true.
5) Create a new condition that checks your placeholder field to see if the value is something other than NULL
6) Create a new Process may look something like this.
Double click on the Action "Set SpecifiedFieldToNull" and in your placeholder field literally type NULL. Also you may need to make that an automatic action instance instead of action instance, green field instead of blue - can't recall offhand. You will also need to make your placeholder field temporarily visible in window manager.
6) Create a new Query for use by the step below, the query should return only tickets with a value other than NULL in your placeholder field. These results will be used in the step below.
7) In Console Administrator / Schedule Manager create a new schedule that runs as needed.
For the Query - choose the query you created above then in the Action choose the process your created above.
When this run it should fire off the process using only the results from the query above.
Since you are setting the placeholder field to NULL each time, those tickets would be excluded on the next run unless that value had been updated again.