fix: Hide new pageIndex logic behind flag

[gethinwebster]

Issue #, if available:

Description of changes:

Revision of #99 so that the new logic is behind a flag, as the change turned out to be breaking for some customers.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.22%. Comparing base (b6007dd) to head (9d67b51).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #103   +/-   ##
=======================================
  Coverage   99.22%   99.22%           
=======================================
  Files          14       14           
  Lines         515      515           
  Branches      183      183           
=======================================
  Hits          511      511           
  Misses          4        4           

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