Dri coat

Can anyone shed light on this problem,
After many years using the traditional plastering sand and cement with additive, I have started to use thistle dricoat, I have really took to using it but when it is trying out especially when meeting plasterboard I seem to be getting a salt line. Even after removing plaster 1.5m high then installing a membrane system , the substrate was in dry condition after about 300mm . Is this normal, I assume that once it has completely dried out you just need to brush off and decorate or would you brush sbr on the area.
Thanks colin

In theory it is not supposed to come into contact with gypsum, obviously once dry it can be skimmed with board finish. I wouldn’t worry and just rub off the salts then skim the dri coat first then skim the boards. If you have the option to float before you board then let the dri coat dry/cure then board up to it.

Hi had a job in matlock, has done the same heavy salt contamination even though substrate was dry block work and applied a salt neutralise