Rear drum cylinder pistons

Hi all

First post to the forum.

After lots of searching I have come to ask the experts.

I have a 2002 Fabia hatch 1.9 SDi. When renewing the rear brake shoes, should the little lug on the cylinder piston be at the back to stop the shoes falling off the back of the piston, or at the front to stop it coming forward.

The reason I ask is that on both sides the lug is at the front, but the shoes seem to fit almost at the back edge of the piston

Cheers