API - GET - Collection inconsistently returning either single INT or array of INT for a relationship

One of my collections has a relationship to another collection. This relationship has always resulted in returned data/json like example 1 below. Now, it looks like some of the records have this relationship saved as example 2. I’ll be submitting a ticket for this but wondering if anyone else is experiencing this and why it could be happening. This behavior is new and there is certainly a difference between expecting a single INT vs an array of INT that only has one value.

Example 1:
“ExampleAttribute”: [

Example 2:
“ExampleAttribute”: 87252,