The 10-furlong heat was originally pencilled in for Newmarket on June 5, should racing resume as hoped on June 1, but has now been switched to Haydock on June 7.
The move to Merseyside has pleased Fellowes, as his runner has shown a preference for some ease underfoot, including when finishing third in the Hampton Court Stakes at Royal Ascot last year.
Watch how Regal Reality won the Brigadier Gerard Stakes last year
He said: “That put a big smile on my face. I couldn’t believe it when I read where the race had been moved to as that was the only one I wasn’t 100 per cent happy about.
“Haydock is a lovely, flat track and if you’re going to get rain in any part of the country, you’d have to think it’s more possible in the the north west.
“He’ll be trained for the race, but much like if it had been at Newmarket, I wouldn’t run him unless I was 100 per cent happy with the ground.”
Fellowes has high hopes for King Ottokar and will take a patient approach with the Motivator colt, who has won two of his six starts.
However, Fellowes could consider a possible international trip next year, with the Sydney Autumn Carnival on the radar after British runner Addeybb secured double Group One gold this year, in the Ranvet and Queen Elizabeth Stakes.
The Newmarket trainer added: “It’s early in the season and there’s no point in rushing with him.
“We have got half an eye on taking him to Australia for the Autumn Carnival and the races William Haggas won this year.
“Sydney in April could suit him if he’s up to it, as the ground tends to be soft.”
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