The Jonas Brothers move some tour shows to smaller venues 

Variety quotes, at length, from an Instagram post from the band, but either said post is no longer extant or we have in the blink of an eye fallen into technical illiteracy. So, here is the full IG caption as quoted by Variety:

To the fans, we’re so excited to get out and be with you for our 20th  Anniversary Tour! Every decision we make is with you in mind, ensuring the best experience for our incredible fans. We’re making some venue changes, but rest assured, all performances are still happening on the same dates and in the same cities. We’re pouring our hearts into making this the best tour we’ve ever done, We love performing for you and sharing this journey together… We apologize for any inconvenience these changes have caused and we can’t wait to see you on the road!

The cities in which a stadium concert is no longer happening are Los Angeles, Philadelphia, Detroit, Chicago, Washington D.C., and Dallas. All of those were going to be baseball stadium shows, and all of them have moved into arenas or amphitheaters. The stadium shows that remain, for now, are at Fenway Park in Boston and at MetLife Stadium just outside New York City in New Jersey. That's the brothers' hometown show, though, so that one may be fine. There's also Hersheypark Stadium in Hershey, Pennsylvania, but that is a music venue, if a sizeable outdoor venue. We mean, Simple Plan and Avril Lavigne were able to have a show there.

Now, while all these replacement shows are in the same cities on the same days, it is important for ticketholders to know that these stadium shows have been full-on canceled, and these new venues are considered new concerts which require new tickets. The ticketholders will get full refunds, and when the tickets for the new shows go on sale this upcoming Wednesday, they will get "priority access" to buying them.

Hey, so the Jonas Brothers bit off more than they could chew. They thought they could sell sufficient tickets for several stadium concerts, and they couldn't. Being able to plausibly sell out an arena is still impressive. The 20th anniversary tour will still be a big event for the brothers and their fans. It just won't be happening at Dodger Stadium or Wrigley Field or the like.

(h/t Variety)