I think its hard to say. If it were me, I would tip them. Keep them trimmed down and see how things were working out in about 2-3 weeks. When I got my 12 week old yorkie both her ears were floppy and down. A couple weeks later one was up, one was down..they would take their turns.

But now their stronger and they pretty much remain up all on their own. I never ended up having to tape.
How big is your puppie?
Out of the two that I have, the one whose ears were floppy is the smaller one. she will be around 4 1/2 lbs as an adult. I initially wondered if the floppyness had anything to do with her being smaller but now I'm not so sure. Its probably just genetics. Did the parents of your pup have straight ears?