Front left suspension knocking

My 2010 1.2htp with around 84,000miles, has developed this knocks when driving over poor road surfaced, bumps. Strangely it won't knock when I push down but will when I pull up on the wheel arch.

I have jacked the side up and thoroughly inspected the following

Top mount / strut bearing.

Drop link.

Shock and spring.

Lower arm bushes.

Grabbed the wheel at 12 and 6 o'clock and rock it to check for ball-joint or wheel-bearing play.

Grabbed it at 3 and 9 o'clock and check for steering play.

All seems fine.

Also I did replace the drop links last year, but all other suspension parts are the original from new. I have done all the repairs and maintenance since owning it for the last 16 years, but I'm not sure what other checks on this knocking I am missing out. Any help and suggestions is welcomed. Thanks

I have uploaded a very video of me lefting the wheel arch to reproduce the knock.