Can't wait for this summer's massive Black Sabbath reunion? Looks like you're going to have to wait even longer. Sabbath's previously announced comeback European trek has been put on hold as Tony Iommi continues to battle lymphoma, with only one date -- a June 10 appearance at the U.K.'s Download Festival -- going ahead as scheduled. For the rest of the announced tour dates, singer Ozzy Osbourne will now be joined by a selection of "special guests" with a band billed as Ozzy & Friends.

A press release from Black Sabbath reads as follows:

"So as not to let the promoters and fans down, Ozzy Osbourne will now perform the majority of the previously scheduled Black Sabbath dates (both festival performances and the headlining shows) billed as Ozzy & Friends. These 'first ever' Ozzy & Friends shows will feature appearances by 'special guest' musicians including Geezer Butler (who will join Ozzy for a special Black Sabbath set as a show of respect and support to their friend, Tony Iommi) and longtime former Ozzy band member Zakk Wylde. In addition, Ozzy will be accompanied by longtime collaborator and friend Slash at select shows, with other 'special guests' set to join the tour at various stops along the way."

But to some Sabbath purists, the reunion tour wasn't even a true reunion, as Bill Ward remains on the sidelines. The drummer revealed last month that he's currently not taking part in any Sabbath activities due to a contract dispute, although he does want to join the comeback -- whenever it happens -- and remains hopeful a resolution can be made that will allow him to take part.

In a note posted on his official website Friday (Feb. 17) likely before the reunion tour was put on hold, Ward wrote: "Last week, we sent further communication to the attorney handling the [Sabbath reunion] negotiations to try to reach an agreement. At this time we are waiting to hear back. I remain hopeful for a 'signable' contract and a positive outcome."

So while Ozzy is announcing the Sabbath reunion is being delayed while Iommi continues his fight, some wouldn't even consider it a true reunion until Ward is invited to take part. But whatever you want to call it, it's happening one night only, for the lucky ticket holders of the Download Festival.

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