No. IEPs do not expire. A new IEP must be written annually, or more frequently if necessary, or at parent or teacher request to replace the current IEP. If you and the school disagree on placement or services, the last agreed-upon and implemented IEP remains in effect. The disagreements may become the basis for a request for due process.
Once you file for due process, your child must remain in his current educational placement until the disagreement is resolved. [34 C.F.R. Secs. 300.324(b) & 300.518; Cal. Ed. Code Sec. 56505(d).] See Chapter 6, Information on Due Process/ Compliance Procedures.