"Wonder what'll happen when a concerning variant comes along? Whether they've washed their hands of it now, or they'll be willing to roll back on some of this?"
Surveillance will continue by the sounds of it, just in the scaled back way that we track other diseases of concern, so variants will be monitored. There will be other variants, that's pretty much certain, and maybe the next one will be worse (much like you sometimes get a bad flu season I suppose), but we can't continue on high alert indefinitely with all the damage that causes just in case it is. I think the hope is that the high level of immunity will protect against future variants, and although it hasn't been explicitly stated the high levels of infection giving hybrid immunity will also make the population more resistant to future variants. If/when they do emerge I expect the vulnerable will be offered vaccines, but I'd be surprised if there was a wholesale return to restrictions given everything we now know about the harms.