YMTC was getting ready for a second plant and that requires additional orders, which a big client like Apple would bring. But once you lose all the American clients at the same time + see lower prices across the board, then it's going to be tough.
Things are already tough from the point of view of servicing your American tools. Then you factor in losing your oversea clients and memory market prices collapsing, not a great time for YMTC right now.
I don't think in semiconductor or any capital intensive industry,manufactures would just build an expensive plant based on empty promise of order,that would be way too risky. Unless there are some kind of written contract,which clearly defines penalty if one side breaks the contract.
I don't think YMTC's plan to expand production has anything to do with Apple. YMTC had this three phase production expansion plan since day one if I remember correctly. I don't think YMTC ever targeted oversea market,or have any plan to sell it's products outside of China in near term.
Again,YMTC isn't a public company. We don't know the real situation of the company other than speculation,that gives room to all kind of rumors regarding this company circulating on internet,domestic and overseas.
Memory is a typical cyclic industry,and it is in downward cycle now. So time is tough for YMTC that's for sure,but the biggest challenge for YMTC would still be transition to domestic equipment,which takes time.