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The 19th seed, who won 6-3 5-7 9-7 to reach the last eight, is due to marry her fiance, Miso Navara, in Bratislava.
"We chose this (date) because I never saw myself as such a great grass-court player," the 27-year-old said.
"We can postpone it. I'm still here and I'm playing my match tomorrow."
Cibulkova now plays Russia's Elena Vesnina in the quarter-finals.
She added: "We are still going to keep this date. We will see what's going to happen.
"If I would win tomorrow then we will change it. Then we will have to postpone it because it will be a lot of rush."
Cibulkova's win over 2012 finalist Radwanska, the third seed, lasted two hours 59 minutes.
The Slovak served for the match at 5-4 in the second set and survived a match point in the 12th game of the third before successfully serving out on her third match point against the 27-year-old Pole.
Cibulkova is on a nine-match winning run after victory in the Aegon International last month and beat 2014 Wimbledon runner-up Eugenie Bouchard in round two at SW19.
Dominika Cibulkova beat Agnieszka Radwanska in a match lasting almost three hours to move closer to the Wimbledon final, which takes place the day she is due to get married.