Londoner Whyte was stunned by his Russian opponent during their first encounter at Matchroom's 'Fight Camp' in Essex back in August, being knocked out in the fifth round and losing his WBC interim title in the process.
The duo were due to lock horns again in November, only for the fight to be postponed after Povetkin contracted Covid-19.
A struggle to recover then saw a proposed January date moved, with Whyte finally scheduled to get his chance at revenge on March 7 at The SSE Arena, Wembley.
However, Hearn admitted this week that there could be further delays caused by Covid-19 travel restrictions, with Whyte training in Portugal - a country on the UK’s ‘red list’.
Providing a further update on the eagerly-anticipated fight before Saturday night’s European welterweight title clash between David Avanesyan and Josh Kelly, the Matchroom Boxing chief confirmed it had now been moved to March 27, with Gibraltar as the new, unusual venue for the entire card.
“Dillian Whyte is out training in Portugal, we know that is a red list country. Funnily enough he didn’t fancy the hotel quarantine,” Hearn told Sky Sports.
“We were trying to get him into Spain, but the borders are closed down so unfortunately we’ve had to move the event.
“Just three weeks, March 27, to Gibraltar. The Rumble on the Rock. This is wild, this is crazy, this is going to be epic.
“We’re moving out of Wembley for this event, we’re all flying out to Gibraltar, on the rock there. It’s going to be a momentous heavyweight occasion.
“Wild, wacky, a little bit off the cuff, but in these times we’ve had to do something different.”