MATLAB: Write output list from a loop

Question

I have two .mat files (A & B). Once find a first occurrence of the defined index. I want to write them out to a array or table.

The following code only write the last entry, and I played with it for a while and still can not get it right. Appreciate help on this.

tstart=datetime(A.StartUTC,'Convertfrom','excel');  
tend=datetime(A.EndUTC,'Convertfrom','excel'); 
UTCtime=datetime(B.date, 'InputFormat', 'yyyy-MM-dd HH:mm:ss');
    for Pf_No = 1:size(A, 1)   
        Day=char(A.Day(Pf_No));
        Scenario=char(A.Scenario(Pf_No));   
        Idx=(UTCtime>=tstart(Pf_No) & UTCtime<=tend(Pf_No) & strcmp(B.Scenario,Scenario));
        X = UTCtime(Idx);
        BLK=find(isnan(B.b1(Idx)) | B.b1(Idx)==0 | B.b4(Idx)<4, 1 , 'first');     
        BLK_Time=X(BLK);
        Breaklock_list={Day Scenario BLK_Time};
    end

Answer 1

          Breaklock_list(Pf_no, :) = {Day Scenario BLK_Time};