The uncertainty is somewhat artificial, though. Unless someone who took the same itinerary in the very recent past chimes in to tell you exactly how they managed to get the boarding pass for the HV sector, nobody you ask (online, on customer support, on here) will be able to tell you exactly how the procedure will unfold, because KL-to-HV transfers aren't frequently documented on here, or elsewhere. But that doesn't mean that the procedure is uncertain or that your connection is not viable. Hundreds of people do this every day without issue. (I've never done a KL-to-HV transfer, and I'm guessing the majority of the FlyerTalk audience hasn't either; and I'm pretty certain none of the customer service employees you speak to will have done so either, which is why none of us can spell out for you what the precise sequence for your particular journey will be. But that unfamiliarity with the specifics should not be seen by you as being a point of concern)

You will make this connection with ease. You will get your boarding pass. Whether that means you will get it when you check in online or in the app, or will get it at the desk at LBA, or will need to visit a self-service kiosk in AMS I cannot say - but your connection is very easy and you will make it.

Don't worry.

But please do return and give us a full account of your experience. Unfortunately, we get lots of questions on here where posters never complete the story by coming back to tell us how things worked out. And it will help us too.

(My guess is that you will receive both BPs upon checkin - whether online or at LBA - and your bags (if any) will be safely tagged through to your final destination)

Enjoy your trip! (And stop worrying!)