Yes, you are right. The value shown on the chart by SG is the High of trigger candle. This is a slightly older AFL which shows the Buy price as "above high of Trigger". The later version shows it as 10 paise above the trigger high. Therefore, for TATAPOWER it would be "Buy above 99.65". You need not go by the value shown by the AFL. SG is marking the correct prices on charts in the form of a horizontal line.
-Anant