Collecting Australia Self Adhesive Sheets?

This is a self adhesive sheet from 2001 and there is no sign of gum bleeding. There are another 30 or so that are perfect condition.

Has anyone got a S/A sheet that is older?

Have you had any trouble trying to store S/A sheets in your collection?

Another S/A sheet which is much larger from 2009.

I don't know if they use the same adhesive, but I have US self-adhesives going back to 1991 that show no problems.

Thank you eyeonwall.

I am not greatly experienced with keeping S/A sheets.

Some months ago I purchased a real mess of S/A booklets that were all stuck together from the gum bleeding from behind the stamp.

Some very warm water saved all if I remember right.But all the gum had to be removed.It did take some time to do it.

So this question has been in the back of my mind for some time now.

I think our 1st modern S/A was in 1993.

I've seen some from one of the European countries that bled (wasn't France or Germany or Switzerland or Sweeden, might have been Denmark or Finland or ???)