Making slits (position during ceiling installation)

What do you still want to do with Sat today? - in any case, Sat and LAN do not belong in the same "empty" conduit with power cables. You can forget about pulling cables later through the straw-thin protective tubes anyway.

I am just asking myself the question everyone asks with this topic: LAN and SAT cables through conduit or directly under plaster. For the former, I would have to extend all the corresponding conduits again.

There are M25 connectors for your pipes. Cost about n €. I still don't understand why it is done so short. It was known what needed to go there. Then you just leave it longer directly? I mean they cost 50 cents per meter. Even with a few meters waste, you won't go broke.

You can forget pulling in the straw-like protective tubes anyway.

I actually have to disagree with you here. I assume they are M25 pipes. That works wonderfully. Even duplex is possible without much problem. You just have to get the wire through the pipe. The pulling is less problematic.

I only say "bend radius" and "stability against deformation," we just had that the other day with a thick sewage pipe hose between the house and the garage. My skepticism towards the combination of protective pipes and [Gottvertrauen] has its reason.

There are plug couplings for all common empty conduits. Simply plug them on and thus extend the empty conduit.