I don't think it is at all and her being at Sziget seems very unlikely to me. Checked the profile, there are are a lot of tweets that turned out to be fake so don't trust that account.
Also, I am a fan of house music, but this year I mostly see techno on the lineup, especially 'I Hate Models' or '999999999' type techno. Last year we had Four Tet, Fisher, Barry Can't Swim, Dom Dolla and I really hope to see more artists like that if we are getting more house, and less techno DJs
It's bullsh*t. She's playing in Toronto on the 5th of August (literally one day before Sziget starts) and then she has a few dates in South America at the begginig of September. There's no way she's coming to Europe in between those two legs when she has UK tour planned for October.
Yeah Chappell’s sole U.K. shows thus far have been a short run of tiny shows that sold out instantly before she’d even properly taken off so demand for her will be massive. Just need to see some of the crowds she’s pulled at her US shows to see how popular it’ll be, and I’m sure she’ll get the same level of insane fans camping up at the front of the stage all day as Lana did.