[REF] move definition of important values & retrieval outside payment…

[eileenmcnaughton]

Overview

Very small code cleanup

Before

Code less readable

After

The squirrels ate my code

Technical Details

The concepts of billingMode is deprecated - goal is not to have separate handling for each one

Comments

There are some payment processor related issues in this code but it's ruthlessly mind bending so we need to feed a few squirrels first

[civibot]

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[eileenmcnaughton]

@mattwire are you ok to merge this - it's just part of trying to get rid of the isNotify loop