Does the 240 day rule have precedence over 5 Year L1B limit?

I am here in the US on an L1B visa. The current I94 on my L1B visa expires on 13-March-2014. Taking in to account my previous stays, my employer has filed an extension requesting time from 13-March-2014 to 10-May-2014 (extension of 58 days). By 10-May-2014, according to my employer, I will reach the 5 Year (365*5 days) limit - maximum allowed stay limit on an L1B visa. This extension was timely filed way back in 20-Nov-2013. On Feb 13th 2014, USCIS has pushed my case to RFE. Assuming I would be given a period of 90 days to respond to the RFE (~ 11-May-2014), and I respond to it before the deadline, am I allowed to stay in the US and work for up to 240 days or until a decision is reached by USCIS - which ever comes first, even though I surpass the 5 year authorized stay time limit on 10-May-2014? Or should i exit US by 10-May-14?