How long does shareable links last for? / My shareable link no longer works?

HI Guys, brand new to Adobe XD and doing tons of lessons and learning fast. 

Made a quick fun little project and created a public shareable link (presentation option). It worked perfectly and then in the last week or so the link populates the 1st artboard and then gets 'stuck' after displaying the 2nd artboard. 

The file hasn't had any changes, and in preview mode still works as it did before.

The purpose of my question is to establish if these shareable links are permant or temporary? I ask, to know if I want to create a 'Portfolio' with Adobe XD, can I share it as a public link indefinately. I don't want to advertise something as a link to a portfolio if it doesn't work... 

Or is my shareable link in this example gone funny. I have plenty space in the cloud as I only have 2 files uploaded.  

This is the public link in question:

https://xd.adobe.com/view/f1e53cd8-c326-4b21-5aa9-84fd64cc619f-87d4/?fullscreen&hints=off