Awning/Terrace covering

I own a flat in Mumbai, 1st floor with a private terrace (only accessible from within the flat). I have put a retractable awning on the terrace to protect myself from bird droppings and other garbage which members from 6 floors above me keep throwing off their balconies. The members in flat above me on second floor are asking me to take the awning lower almost to human height because it spoils their view. I understand from mcgm DC regulations the following is allowed: In features permitted in open spaces (e) (i) A chajja, cornice, weather shade, sun-breaker; at lintel level only projecting not more than 1.2 m. from the face of the building. No chajja, cornice, weather shade, sun-breaker etc. shall reduce the width of the required open space to less than 2.5 m. Further Chajja, Cornice, Weather Shade, sun breaker or other ornamental projections etc. shall be permissible upto 0.3 mt. in Gaothan area for the plots adm. upto 250 sq.mts. However in case of redevelopment of cessed building, where marginal distances are less, chajja projection maximum up to 0.45 m. may be allowed. (06012012) What is this lintel level? How to measure it in a multistory apartment? In my understanding it is the beam running across above the window. That beam touches my ceiling height which is about 8.5 ft? how to understand and enforce my rights here?