Liu Sicheng's condition was serious. If they completed everyone else's scenes first, leaving his for when he had recovered, it would inevitably delay the entire film's progress. It is said that 'for joints and bones, a hundred days are needed to heal.' By the time he was fully recovered and ready to film, the momentum would have long passed!
With such a delay, the public would gradually forget their anticipation for the film.
After all, everything relies on the principle of 'striking while the iron is hot, with the second effort waning and the third exhausting.'
However, if they didn't wait for him to continue, but instead replaced the actor, where could they find a suitable male lead in such short notice who could take Liu Sicheng's place?