Find & Replace doesn't work on array formulas

Here’s the file.

find-replace.ods (11.9 KB)

I want to change the formulas from <500 to <400, I’m not getting errors but it doesn’t change the formula when I try to change it. Is there a way to do this correctly?

Read the online HELP for topic “Editing Array Formulae”
special key presses are required but it will work if you follow the instructions
it uses ctrl-/ and ctrl-shift-enter
regards

that only work on a single selection of array formula, it doesn’t work on multiple selection of array formulas or when I use find & replace (ctrl+h)

Is there a reason why you don’t put your variable in a separate cell?