SSS_TIME_LIMIT_EXCEEDED - 3600 seconds

We import a few thousand records of a custom record type each day. Once these records are in our system a scheduled script processes them and categorizes them by selecting an option from list/record field on the record.

I have 4 SSS_TIME_LIMIT_EXCEEDED errors from last night. The script used between 4000-6000 units. Each error says the script ran for 3600 seconds.

Here is my code:

function scheduledMEUpdate(){    var context = nlapiGetContext();   var searchAgain = true;   while(context.getRemainingUsage()>15 && searchAgain){   var MEs = getMEs(); //10   var MEsLen = (MEs != null)?MEs.length:0;   if(MEsLen < 1000) searchAgain = false;//search returns 1000 results... so needs to be triggered multiple times   //update each record:      for(var i=0;i<MEsLen && context.getRemainingUsage()>4;i++){    //if the ME has a GROUP then use GROUP join to get info else USE Item join to get info    var id = MEs[i].getId();    var cols = MEs[i].getAllColumns();    var adPl = MEs[i].getValue(cols[2]);    var itPl = MEs[i].getValue(cols[4]);    if(adPl == ''){     if(itPl != ''){      nlapiSubmitField('customrecord_mexp',id,'custrecord_mexp_prod_line2',itPl);//4      //nlapiLogExecution('audit','INFO ','ME: '+id+' | Item PL: '+itPl);     }    }else{      nlapiSubmitField('customrecord_mexp',id,'custrecord_mexp_prod_line2',adPl);//4