In Europe & the UK a planer / thicknesser is a combination machine which does the jobs of a jointer and a planer (In US terms)
I've used two kinds of these machines but am unsure whether the feed direction should be different when planing (stock runs agains a fence above the blade) and thicknessing (stock is fed beneath the planer surface on an adjustable bed and rollers press the stock down and feed it through the machine.)
On the machine I am currently using the manual specifies the feed direction for thicknessing but not planing. I noticed that when planing the blades wanted to grab the stock and move it in the direction of feed. I therefore wondered if the feed direction should be reversed? It is very likely the blades also need replacing as I doubt they have been replaced for several years.
The machine is a Rojek MSP310M