Episodes

The episodes in this series include:

First ten

 * The Locked Door Mystery debuted 6 January 2018 on YouTube and 23 March 2018 on CBC. It is episode 8
 * The Mischevious Mind Reader debuted 6 January 2018 on YouTube and 24 March 2018 on CBC. It is episode 9
 * The Mystery of Alex's Weak Kick debuted 6 January 2018 on YouTube
 * The Mystery of the Haunted Beauty Salon debuted 6 January 2018 on YouTube and debuted 13 January 2018 on CBC
 * The Mystery of the Raspberry Rustler debuted 6 January 2018 on YouTube
 * The Mystery of the Raucous Racket debuted 6 January 2018 on YouTube
 * The Mystery of The Run-down Robot debuted 6 January 2018 on YouTube and 31 March 2018 on CBC. It is episode 10.
 * The Not-As-Great Pizza Problem debuted 20 January 2018 on CBC, and debuted 6 January 2018 on YouTube
 * The Static-y Stumper debuted 6 January 2018 on YouTube
 * The Thirsty Camanel debuted 6 January 2018 on YouTube

Second half

 * Episode 11: Out of the Blue debuted 11 January 2018 on YouTube
 * Episode 12: The Cookie Caper debuted 18 January 2018 on YouTube
 * Episode 13: You Ain't Seen Nothing Yeti debuted 25 January 2018 on YouTube
 * Episode 14: The Mystery of the Secret Code debuted 1 February 2018 on YouTube
 * Episode 15: Animal Magnetism debuted 8 February 2018 on YouTube
 * Episode 16: Message in a Bottle debuted 15 February 2018 on YouTube
 * Episode 17: The Mysterious Meltdown debuted 19 May 2018 on CBC, and debuted 22 February 2018 on YouTube
 * Episode 18: Geocache and Release debuted 26 May 2018 on CBC, and debuted 1 March 2018 on YouTube
 * Episode 19 The Mystery of the Blob Monster debuts 2 June 2018 on CBC, and debuted 8 March 2018 on YouTube
 * Episode 20 The Mystery of the Magnifical Mau-Mau debuts 9 June 2018 on CBC, and debuted 15 March 2018 on YouTube

Season 2
23 February 2019 at https://www.youtube.com/watch?v=CLsJFekHu_I&list=PLPZ40gM7aDFDfSQi4kbEaHmQtfyhqmn-k&index=22&t=0s was "SNEAK PEEK Addison Season 2" which was Mystery of the Shrinking Rink.

New episodes after the initial run of 20 did not begin broadcasting until August 2019 and were not released early on YouTube this time around. They include:

2019:
 * Aug 16 Missing Pteranodon ep 10
 * Aug 17 Birthday Brainteaser ep 12
 * Aug 20 Runaway Robots ep 14
 * Aug 21 Missing Kitty ep 15
 * Aug 22 Sneezy Snuffle-ies ep 16
 * Aug 23 Missing Mammoth ep 17
 * Aug 24 Suspicious Circle ep 18

2020:
 * January Fog Mystery ep ?
 * Feb 1 Perplexing Parrot ep 28
 * Feb 13 The Mystery of the Number One Mean Girls Detective Agency ep 20

Numbers 1-9/11/13/19/21-27 have not been announced yet. One of them presumably is "Shrinking Rink" though.