The two-year temporary disability limit under Cal. Lab. Code § 4656(c)(1) is four years post adoption, and some of the major issues relating to it have been addressed in a few published opinions.
 
1. When does the 104 week TD limit start? It's the date on which temporary disability indemnity is first paid, and not the date for which temporary disability indemnity is first owed, according to the WCAB en banc decision in Hawkins, v. Amberwood Products, State Compensation Insurance Fund (2007 en banc)72 Cal. Comp. Cas 807; 2007 Cal. Wrk. Comp. LEXIS 167.
 
2. What is the effect of delay in payment of TD on the 104 week limit? Delay of payment of TD does not come within the limit, according to Hawkins.
 
3. Does the limit restrict the amount of TD that can be paid to 104 weeks or is the limit on payment, not the amount? The 104 week limit limits the payment period, not the amount of TD paid, according to Hawkins.
 
4. Is an applicant automatically entitled to 104 weeks of TD for each injury? The statute is clear that the limit is on aggregate payments within 104 weeks. The "aggregate" modifier allows the limit to apply if there are any payments within 104 weeks. So an applicant could receive two weeks of TD payments, return to work for 100 weeks, and if then TD again, would only be entitled to another two weeks.  Everyone has accepted that as the result of the plain and clear language of the statute. 
 
5. How is the limit applied to TD from multiple injuries? Where two injuries cause TD concurrently, then the two year limit on TD runs concurrently. The court in Foster v. Workers' Comp. Appeals Board (2008) 161 Cal. App. 4th 1505, 75 Cal. Rptr. 3d 272, 73 Cal. Comp. Cas. (MB) 466 set a standard that looks to the medical evidence to determine whether TD is due to one or more injuries. If TD from multiple injuries occurs at the same time, then the two-year limit runs concurrently.  If TD from multiple injuries results in separate and distinct periods of TD, then the TD payment limit from each injury would not run concurrently. It's a question of medical fact.
 
6. How does the limit apply to IDL that is paid in lieu of TD? Because IDL is statutorily defined as the equivalent of TD, the two-year limitation under Cal. Lab. Code § 4656(c)(1) necessarily must apply to both IDL and TD, according to Brooks v. Workers' Comp. Appeals Bd., (2008) 161 Cal.App. 4th 1522, 75 Cal. Rptr. 3d 277, 73 Cal. Comp. Cas. 447.
 
7. Does EDD come under the TD limit?  This issue remains unresolved.
 
The interpretation of the TD limit is proceeding relatively rapidly, which will facilitate dealing with the TD limit in day-to-day case handling.
 
I'll be writing a LexisNexis Expert Commentary on the subject and commenting on all the key cases that have interpreted this statute. Stay tuned for details.