As you mentioned, the best time to prune is Sept/Oct. Perhaps you can plant a magnolia on your side, or some evergreens?

We have a 4ft 6 wooden fence or there abouts....3 different sections in age & height The nbr had a 30 yr old magnolia tricolour & it was always full of flowers but 2 main branches broke after a storm. It was 25ft high. On our side there is a magnolia stellata & an acer but they are only 4 ft high. Lower down we have an enkianthus ,old rhododendron & spindle tree. By the birch tree we have a 2 ft high magnolia & then lilac lower down. The nbr removed all plants to fence ht. His priority is lawn for kids & patio. So wait & see.
Stuff he removed was in the main evergreen. You only wonder when its gone as to what it was.

Yep, that happens. My neighbor removed his wild grape vine that hung over my side & I used to make fabulous grape jam & tie dye Tee shirts from the purple grape skins. I would have art lessons for the kids. That's all over lol!

Unbelievable Bill isn't it.

Don;t take too much off the lilac if its yours - they should be pruned, if they need it, immediately after flowering, so if you cut off a lot now, you won't get many flowers next spring.

Hm. One of the lilac branches has moved from the fence area & moved 45 degrees. Few days later its not 90 degrees to where it was on the grass......no support so it is bye bye. Filled a green wheelie bin, No choice really just odd. There are lots for the chop after flowering. I spotted a varigated holly.2ft high 7 yrs old. 2 hydrangers simply dissapeared (my side) the lilal is greedy fow water so I guess its hard for others to survive. I have a spring planting scheme with b bells,daffs, xmas roses & snake plants & wood anenomies but the lilac is the height. I also have variegated ivy an acer ,quince & a few other players.....