I just found this by accident, because it wasn’t announced (surprise…). Because how frequently do any of us go back into our profile to make changes?
Addendum: I just tried it and it doesn’t seem to work.
This is on the app:
Hi @alegría
Just confirming that I’ve seen your post - I’ve reached out to the team and will pop back with any updates about this.
Jenny 
Just checked and yes, I see this, it’s new. It’s just worded differently though and doesn’t mean anything different to how it was before. It shows your inputted availability that you enter as highlighted and booked dates crossed out.
@alegría, how very strange.
It would seem very odd that THS actively encourage Pet Parents to contact unknown housesitters to ask of availability/interest for a specific listing date. This topic has been discussed extensively in THS Forums and - consistently with our own experience - then it seems typically a waste of time. Worse still it may create unrealistic Pet Parent expectations. If Pet Parents spent more time creating an attractive, complete listing … rather than cold-contacting sitters … then they will likely achieve a better outcome.
Of course, they can do both..
Some of the best sits I’ve had have been with people who “cold-called” me. There’s something to be said for starting from a basis of feeling actively wanted…
Hello!
Just popping back with a response from the team:
You’re right, it’s not something we really highlighted to members.
That availability section has been around for a while, but over time we’ve found that the best matches usually happen when sitters apply for sits they genuinely like, rather than owners searching for available sitters.
You can still use it, especially for sending invites, but it’s not how most sits get matched these days. That’s why we’ve spent more time improving the application experience instead.