PCN for parking in a restricted street

At the back of my business premises is a narrow back street (Dugdale St, Burnley).

https://www.google.co.uk/maps/@53.78...7i13312!8i6656

For over 30 years all the businesses have parked at the back of the Manchester Road premises without any challenge.

There are yellow lines on both sides, but the side where we all park they are broken up and wavy lines.

I've now had four tickets and they rejected my 1st appeal, so am getting desperate / worried.

There are no signs saying anything about any restrictions.

My back wheels are on the broken lines.

But what I'm asking is can I challenge this re the lines being broken, lack of signage, non straight lines or the fact that a precedent has been set by it being allowed for 30 years +

Thanks