Oh, wow! That’s a huge amount of time. Ensure yourself to disable Realtime in viewport, so this may reduce the performance. Anyway, Epic should obsequiate you with an RTX card 
But good to know that 5.4 will be faster.
EDIT: Oh, I was wrong with my tests. For some reason, the times was not correct, I don’t know why. I have tried now, twice every version (4.27 and 5.3), and it takes almost the same time to complete (Production, 64 and 32 samples in ini settings): 1:45s-1:46, so it’s so great the time does not increase and it still keeps its good performance!