Hi Megan,
Appreciate you looking into this.
Our update had failed because, I believe another update was being rolled out, which is why we wrongly thought we were on the latest version, if that makes sense!
We reran the update overnight and that was successful.
As a result the error no longer comes up but sadly, I see the explore functionality does not now include the ability to pick an entity and then select the field/criteria.
Never mind, we'll use and/or dropdown boxes.
Thanks everyone for supporting this thread
Now to go and explore what else was in the update!