Can I established glide slope before Intermediate Approach Fix
I have this question when I fly in China. Some times, like one day, I fly on the left downwind of runway 05 in Xiamen (ZSAM) airport for the ILS/DME approach. The altitude at FAF is 2300ft, because of military activity, the tower let me extended downwind and maintain 3900ft. We fly 3NM more after abeam the IF (Intermediate Approach Fix) and then got the clearance to turn to final. At the same times the tower said 'clear ILS/DME approach runway 05'. So after we established the LOC, the G/S almost on the right path,but we are not reach the IF yet. My first officer said that we can establish the G/S and shoot the approach, but I think maybe we'd better us vertical speed to descent and maintain the G/S until we passing the IF. He give me the reasons like that we under the Radar and higher then every minimums, I agree with these but I still think that is not comfortable for me.
So dear controllers, could you give me your opinions whatever under FAR,JAR or some else. Thanks a lot!
Ryan