Either party shall be entitled to terminate this Agreement earlier than as herein provided by serving not less than ONE months' written notice or by paying ONE months ' Rent in lieu to other party provided that the said written notice shall not be served before the expiration of the 【12】 month of the Term of Tenancy.

我知道than 是连词，但than后的 as 相当于什么成分，as相当于something which is provied by doing or by doning sth to somebody ？ as是指租约agreement？？为什么as可以当成名词用？句子的结构是 either party shall be entitled to terminate this Agreement earlier than as(agreement) <which is proviedby doing or by doning sth to somebody> do(省略) ??

而《provided that》则相当于if引导的条件状语从句。

请帮忙分析和解答一下。