it is/was the time that it is/was the frist time that 后接从句用什么时态?

It is the time that 后面用过去式,虚拟语气.
It was the time that,少见.
the first time 用法相当于连词用法,用来引导从句
链接：It’s the first time that 现在完成时
It was the first time that 过去完成时