Sir Elton John may have to wait as long as two weeks before his appendicitis can be properly treated.
The 66-year-old singer was forced to cancel tour dates after falling ill on stage in Halle, Germany on Friday, and is currently on strong antibiotics.
However he must wait for inflammation to reduce prior to being operated on in hospital.
"He is at home and no one knows yet when he can have the operation," a source told British newspaper the Daily Mirror. "He has to just sit and wait. After the op, it is a case of resting up for a while and then he will get back on stage."
The crooner's insurance payout could reach as much as £10 million after being forced to quit his 14-date summer tour that included festivals.
The money will see promoters refunded for tickets, some of which cost around £100. Elton would have performed to around 200,000 people on his cancelled tour dates.
"Artists have insurance for the promoters' liability. Elton is insured so they get their money back or they can have another concert," an insider said.
"It has all been taken care of and will be rescheduled. No promoter will be out of pocket.
"Elton even spoke to some of the festival promoters to apologise because he has been working with them for so long."
The star reportedly takes on about 120 concerts each year.
Before entering medical care, Elton had apparently been telling pals that he felt as if "he was going to explode" for weeks in advance.
Initial tests allegedly specified a virus when he complained of stomach pains.
Elton took a flight home to his native United Kingdom at the weekend to have scans and a blood test which showed he had an appendix abscess.
"I'm lucky to be alive," he commented.