-day release

20:01 Dec 16, 2016 

Thank you, Tony! This fits perfectly into the context. I'll close the question after 24 hours in order not to leave the closing decision to the community :-)

18:38 Dec 16, 2016 

Could you post a "formal" answer, please?

18:10 Dec 16, 2016 

Thanks!

I know I've come across this term before, when we used to have our hotel and had it with various booking agents; but I never paid that much attention, as this side of it wasn't my direct responsibility.

17:54 Dec 16, 2016 

Tony, I think you are right! Thank you for this suggestion!

17:51 Dec 16, 2016 

The text before or after isn't helpful at all: the documents looks rather like a presentation and consists of short pieces of text on various aspects of cooperation of hotels with intermediaries. The two sentences immediately before are as follows:
___________________________
Your revenue manager should establish rates that you would want to offer.
These accounts will probably ask for room only and/or bed and breakfast rates and generally expect a per person per night rate sharing a twin room.

17:45 Dec 16, 2016 

...it's referring to setting aside these rooms for this booking agent, but they will be 'released' again if the booking has not been taken up — in the case of week-days, 72 hours before the date in question, and weekends, 24 hrs before.

BUT you will need to check that I've got this the right way round!

17:42 Dec 16, 2016 

The question really is what does "release" mean - they've left out the hyphen, so it should be "3-day release". The meaning is not entirely clear, though "release" may mean to make a room available to travel agents rather than trying to sell it yourself.
What does the text before this say? That may clarify it.