I am fairly new to beekeeping. I go partly foundation-less and also use only medium size frames. With partly foundation-less I mean that I use foundation frames between
the foundation-less frames, so that they build straight comb. In the beginning
I just had foundation-less frames but I quickly put a few foundation frames in to
prevent a mess. So far it works very well.

In the spring it seems the bees rather used the foundation-less frames to build new
comb and usually use the foundation frames a little later. They also build the comb
very quickly.
This changed now. The bees only build little new comb but they still draw out the
foundation frames when they need the space for honey and brood.
My conclusion from this observation is, that I only put foundation frames or frames with already build comb in to the hives in late summer and fall.
In spring I will use more the foundation-less frames.

I use the Mann Lake PF-125 frames, these are the black medium size frames.

Do you see similar behavior in your hives?
What are your thoughts?