Sir i saw them under the waterpump bridge, main waterpump chawrangi, 2 days back (after 2 o clock afternoon), but i dont know their fix timing, and they are not there all the day. And second location is under NIPA bridge at gulshan (beside Sir Syed University), there i saw them in the morning at around 10-11 am, but dont know the exact timing. I will try to saught out their timings and try to update if possible.