Could any one give any explenation what’s the difference between after the Yichud and the next day???
Yichud is (IIUC) supposed to give the presumption that the couple has been intimate. As such, you would probably be correct.
However, it is well known that (at least now) the couple are usually NOT intimate during Yichud. As such, it is also well known that her status really has not changed since leaving the chuppah. (Which makes me wonder why we don’t just skip the yichud and send a pair of eidim home with the couple after the wedding…)
The next day, OTOH, is a different story altogether.
The Wolf