Integrain DWD/UVC Lifting on Oregon

On some external Oregon timber, coats of Integrain DWD/UVC are lifting down to the bare timber, taking small amounts of timber with it. Most of the problem areas are north and west facing and get a lot of sun. Lifting can start as a result of trying to remove a bubble or when removing old excess lumps of DWD. Original coats would be some 8 years ago when the house was built and more coats applied three years ago and in some cases again this year.

Have been using UVC most recently but now back with DWD. Lifting seems to be more of an issue when the timber is hot. Not sure whether timber originally treated with Dimension 4, which I am now doing. In some, but not all cases, starting point of the lifting is damp affected areas, but coat will lift readily off timber in good condition. Externally the finish looks fine and in most cases, has just been painted.

The question is whether to try and limit the area of the lifting by a gentle approach or to be more aggressive, to try and remove all the coat in an affected area, as I have been doing so far.