What's the deal with...

Years ago Laysons had a fix listed on there site for this, it was for the early-A's.
I remember seeing that in their catalog. They wanted customers to send them their filler tube and Layson's would make some modification. There was no photo and no description as to what the mystery fix was. If it was the seal on the cap all along, I don't know what they would do to the filler tube to fix it.