I filed a support ticket, saying:
Hi, Yesterday challenges 1-5 appeared unlocked, so I began working on challenge 5. When i returned to the game after a break, challenges 3-5 were locked again. I don't mind when they are opened again, but will they be reset, or will the blocks I have dug out remain dug out? I don't want to have lost all the energy I put into it yesterday. Many thanks,
I just received a reply stating:
Our tech team has checked our internal systems and I can confirm that further challenge locations were not unlocked together with the first set of challenge locations at any time.
Further challenge locations will be unlocked as soon as all puppies are collected in the event locations.
I'm sure that I wasn't hallucinating that I had access to challenges 3, 4 and 5 briefly. When I put all the puppies in place yesterday, and got access to those three challenges again, challenge 5 had 100+ blocks dug out...
Not really sure why support are adamant that the challenges weren't unlocked?