FieldFilterTransformer throwing null index 'filter'

Your software
My Mautic version is:4.4.5
My PHP version is:8.0
My Database type and version is:mariaDb v10

Your problem
My problem is:
FieldFilterTransform is throwing the following error:

This only happens when I add a new filter field for a datetime using -18 months or 3 months ago or using the date picker

Going through the code with x debug the array items that I have as part of the array of filters all have 8 items except the final which only has 6. It is missing the filters. Here is a screenshot of the array
image

These errors are showing in the log:

Steps I have tried to fix the problem:
Doing the following fixes the issue
changing line 83 from

 if ('datetime' == $f['type'] && null !== $f['filter']) {

To

 if ('datetime' == $f['type'] && null !== $f['properties']['filter']) {

I am asking if this is okay to do? or is the potential issue somewhere else?