“到那时”（将来式）用英语

可以的！
by then到那时
by that time到那时
by the 24th到 24号那天
By that time he will have been here for ten years．
到下月底，他在这儿就够十年了。
这一时态用来表示在将来的一个特定时刻将成为过去的动作或在该时刻刚刚结束的动作。

bu that time是对的。但是要用将来完成时。

例如：到那时，我就已经从学校毕业了。

I'll have graduated by that time.

by that time
until then
till then

be going to do sth.