Reproduction Steps: You are able to "Cut the line" on a fish even after it has been "caught" as long as the text box has not yet appeared over your head.
(I speedrun other games and tend to mash text boxes. I have accidentally thrown away like 15 fish at this point 
)
Repro Rate: 3/3 times tested
Game Platform: Steam
Game Version: v1.2b-1246
Input Mode: Keyboard & Mouse
#Fishing catch and release
unborn latch
blissful zinc
Hello @unborn latch Thanks for reaching out! Just wanted to confirm the timing—do you cut the line before the animation of holding the fish starts?
unborn latch
In my testing as long as you right click before the white text box with fish size and name appear above your head it will not give you the fish (I am "Cutting the line" after the fishing mini game is completed and the fish is in my player models hand - but before the text box has shown)