Tex. Prop. Code § 64.053
(b) On and after the date on which an assignee begins to enforce an assignment of rents, the assignee is entitled to collect all rents that:
Added by Acts 2011, 82nd Leg., R.S., Ch. 636 (S.B. 889), Sec. 2, eff. June 17, 2011.
Acts 2013, 83rd Leg., R.S., Ch. 453 (S.B. 848), Sec. 5, eff. June 14, 2013.