[Warlock][Demonology]Wild Imps duration (non-combat)

[Ph3n0]

WoW Freakz spell link: https://www.wow-freakz.com/spells.php?spell=104317&&name=wild-imp
Character name: Heresiarch
Bug description: Wild imps should last up to 40 seconds while out of combat, not 20.In bfa they lasted 20 seconds or until 5 fel firebolts were cast.In Shadowlands they last 40 seconds or until 6 fel firebolts were cast. This is not BFA!
Proof 1: https://www.askmrrobot.com/wow/theory/mechanic/spell/summonwildimp?spec=WarlockDemonology&&version=live (the official spellID as the freakz link i posted)
Proof 2: https://youtube.com/watch?v=3cZl3eON_HA:


This lad finishes combat in 5:26 and keeps his imps until 5:57 for 30+ seconds, and more if combat wouldn't have started (so no "20 secs." madness ).
The video may be on 9.2 but there are no changes to this post's problem between Shadowlands patches.