2022.1.1 FeatureWriter isn't sending to output ports (worked in 2021.2)

I am creating a series of small jpeg files using a feature writer with each jpeg getting it's name from a unique value (myRLU_@Value(RLUOID)). I recently upgraded to 2022.1.1 from 2021.2 - things were working until I upgraded.

I have 20 records coming into the FeatureWriter and 20 showing in the Summary port but no records passing through the output port.

The FeatureWriter creates the jpgs but does not pass through the records to the testfilter transformer?

Has anyone else had issues with this in 2022.1.1? Any ideas how to get this running again?

Could this be helpful in diagnosing the issue: FeatureWriter_5: Bulk features are not supported because the expression contains a function call

After playing around some more - looks like the issue is the FeatureWriter using an attribute as the output filename. When I change it to a "hard-coded" value, the records are available in the output port.