"Ban Collie Day” sounds a bit like “bank holiday.” “Ban collie day weekend” was posted on the newsgroup uk.rec.sheds on April 12, 2001. “Yeah. In England you won’t be able use your Sheepdog again tomorrow, because it’s August Ban Collie Day!” was posted on the newsgroup alt.humor.puns on August 25, 2002.

“Do you know why they’re not allowed to show episodes of ‘Lassie’ on the TV today? Because its Ban Collie Day” was posted on Twitter by Sam Gannaway on April 5, 2010. The television drama Lassie (1954-1973) featured a female Rough Collie dog.


Google Groups: uk.rec.sheds
Stockport Beer Festival Moot a no-no (probably)
Austin Shackles
4/12/01
(...)
nicely timed for just after the snowdon moot, if we get to have it.

wot were gonna be the 26/27/28 ban collie day weekend.

Google Groups: alt.humor.puns
Bad news for shepherds again.
nemo-toad
8/25/02
Yeah. In England you won’t be able use your Sheepdog again tomorrow, because it’s August Ban Collie Day!

Twitter
Sam Gannaway
@samganners
Do you know why they’re not allowed to show episodes of ‘Lassie’ on the TV today?
Because its Ban Collie Day.
7:49 AM - 5 Apr 2010

Twitter
Sam Gannaway
@samganners
Why can’t the BBC show Lassie today? Because it’s a Ban Collie Day. #Iworkincomedyentertainment
2:07 PM - 27 Aug 2012

Twitter
StuKershaw
@stukershaw
Relax, dog! I said Bank Holiday, not Ban Collie Day!
1:22 PM - 23 May 2014

Twitter
Alf
@whoelsebutalf
Well, it’s Lassie’s least favourite time of the year again.
Ban Collie Day.
#Bankholiday #bankholidayweekend
4:28 AM - 31 Aug 2015

Twitter
Graham Musk
@Grargemeister
Happy Ban Collie Day, everyone!
The sun is shining so let’s all really get on board with banning Collie’s.....
What?!?!
Oh. BANK HOLI-DAY?!  I get it now.
Today’s #DailyHowl topic is #flowers
Let’s see what stems from that!
3:08 AM - 7 May 2018

Twitter
McCash’s Store
@McCash
We are open on Monday as usual despite it being a Ban Collie Day (groan)
5:37 PM - 26 Aug 2018

29 August 2018, Daily Star (London, UK), pg. 20:
JOKE OF THE DAY
My mates just told me that he couldn’t take his Collie dog on to a caravan park. It was a Ban Collie day. LEO,LEEDS

Twitter
🤣 The Dad Joke Man 😉
@DadJokeMan
What’s he ever done ??!!  I can’t believe it’s a Ban Collie Day Monday !
5:52 AM - 27 May 2019