Ok so I put masonary paint OVER fence paint, whats the worse that can happen?

[RockandRollsuicide]

DH spilt the proper fence paint and finished it off with masonry paint which looks more solid colour and better...

shall we continue?

It will be fine. I did it last year, painted all fences (and there are many) in masonry paint as I wanted it to match with the house. A year on and they still look perfect. Obviously don't know what's going to happen in 3-4 years down the line, but so far so good. And then again, even fence paint needs a touch up after a few years.

It'll brine, they're both water based

Sodding autocorrect !

ooh thanks Mamma and Mumble....

will continue...

fence treatment is a waxy stain. If it was new it will prevent the paint soaking into the wood.

Old fence treatment weathers away so you can re-treat, or a pressure washer will blast it off fences.