Stubhub Viagogo Policy changes after agreement was already in place. San Francisco CA

You can file a suit for just about anything.  That is apparently what someone did.  They filed a lawsuit against them for their change in policy on "Cancelled" events. The issue seems to be a matter of definition as the event in question in the suit wasn't offically "cancelled", it currently is just postponed. Perhaps similar to your situation.

If the courts see cancelled the same as postponed then you likely would have a valid claim. If they see as each being unique then the suit will be tossed out.

However, while the person that filed the suit and the attornies will come out quite well. Any members of the class shouldn't expect a huge payday, in fact I wouldn't even expect a full refund. If it gets that far and there is a settlement 2-3 years down the road a member of the class may end up with a few dollars or perhaps a bigger credit that will be valid for a longer time.

Not sure how Stacey knows if event was cancelled or postponed. Below is a link of Stubhub's new policy with no option on a refund for a product they sold.

https://stubhub.custhelp.com/app/answers/answer_view/a_id/1001856/categoryRecordID/RN_CATEGORY_429/categorySelected/RN_CATEGORY_429

When an event is canceled:

• You don't need to contact us; we'll email you to confirm
• We'll add a coupon worth 120% of your original order to your Stubhub account. You can apply this coupon to one or multiple Stubhb orders in the same currency until Dec. 31, 2021. Just choose the coupon at checout when you order.

The event was postponed NOT cancelled therefore this company is adhering to their policy. 

Your words - Policy agreement stated if event is canceled a full refund or credit will be provided. Event was not cancelled so you are not entitled to a refund.