when did they change Kalista's bind?

{quoted}

it used to be that kalista used the item and u had to pick it up to get bound to her... how long have u been playing the game?

actually no, you've never had a choice, even if you don't click on the spear the binding still forced itself on you FROM release, don't believe me then check back to former board posts and you'll see.

This is the entirety of Kallista's patch history, as copied from the League wiki. Kallista has always had full control over who is bound.

V6.1:

Rend
   Mana cost reduced to 30 from 40.
   Removed: Mana refund when killing one target.
   Clarification: If Rend kills at least one target, its cooldown is reset. If Rend kills two or more targets, its mana cost is >refunded. 

V5.22:

Stats Base attack damage increased to 62.92 from 57.5. Attack damage growth reduced to 2.91 from 3.5. Attack speed delay reduced to -0.1 from -0.05. Base attack speed increased to 0.694 from 0.658. Attack speed growth reduced to 2.8% from 3.3%. Martial Poise new effect: Jump speed is now affected by attack speed slows.

V5.20:

Sentinel
   Announcement: There is currently a bug where some melee oathsworns must attack a marked target twice to >trigger the bonus damage. 

V5.17:

Sentinel
   Passive damage reduced to 10 / 12.5 / 15 / 17.5 / 20% of target's maximum health from 12 / 14 / 16 / 18 / 20% of >target's maximum health.
   Passive cooldown per target increased to 10 from 6. 
Fate's Call
   Cooldown increased to 120 / 90 / 60 from 90 / 75 / 60. 

V5.14:

General Updated recommended items. Pierce / Sentinel Now properly queues up to cast after her basic attack completes.

V5.13:

Stats Base attack damage increased to 57.5 from 53.46. Attack damage growth increased to 3.5 from 3.25. Martial Poise New Effect: Basic attacks now scale with 90% AD instead of 100% AD. Pierce No longer can be cast Martial Poise.png mid-dash.

V5.9:

Martial Poise
   REMOVED: Martial Poise's range is increased by 25% when dashing backwards. 

V5.4:

Martial Poise
   Kalista's basic attack wind-up (the time between starting an attack and it firing) now scales with 66% of Kalista's >attack speed, reduced from 100%. 

V5.1:

Martial Poise
   While Kalista still can't cancel her basic attack, she can now select a different target during the first moments of >her basic attack wind up. 
Sentinel
   Soul-Marked cooldown per target reduced to 6 seconds from 8.
   Soul-Marked duration increased to 2 seconds from 1.5. 

V4.21:

The Black Spear
   Kalista can now re-bind to a different ally any time before minute 3:00. 
Sentinel
   Fixed a few cases of modified/empowered attacks not triggering the bonus damage.
   Minion damage floor reduced from 100 to 75.
   If Sentinel procs on a minion with 125 health or less, it will automatically kill that minion.
   Soul Sentinels no longer see through brush or over walls. 
Rend
   Mana cost increased from 35 to 40.
   Now restores 20 mana if rend kills a unit, up to twice per cast.
   Damage per extra spear increased from 5 / 9 / 14 / 20 / 27 (+15 / 18 / 21 / 24 / 27% AD) to 10 / 14 / 19 / 25 / 32 >(+20 / 22.5 / 25 / 27.5 / 30% AD) 

Fate's Call Ally re-cast delay reduced from 1.2 seconds to 1.1 seconds. Visuals slightly tweaked to emphasize the re-cast delay.

V4.20:

Added.