It depends. The k 2665/8/5 8/5 train from Linfen to Suzhou is called K2665 in Linfen-Sanmenxia West Section and Xuzhou-Suzhou Section, and K2668 in Sanmenxia West-Xuzhou Section. If your boarding station for K2665 is before Sanmenxia, you can get on at any stop after Sanmenxia, which is allowed.

If your K2665 stands behind Xuzhou, you can't get on the bus in advance, and you need to buy a ticket for this section again.

In short, you can get on the bus halfway, but you can't get on the bus in advance.