Expansion Gaps in wooden floor

Layed a solid wood maple floor about 6 weeks ago and, on suppliers instruction, left a 3mm gap every 4 boards with the intention that the floor would expand into the gaps. So far there has been little or no expansion and I'm starting to get a little worried that the gaps will remain. Does anyone know if I need to give it more time or is there something I can do to get the floor to expand into the gaps.

Give it a few weeks and those babies will close up. Maple expands alot so don't worry just yet.

My floor expanded over a period of a year.I left a 10mm gap around the sides and now the boards are right up to the wall.

3mm gaps may have been necessary but during the winter IMO, just a gentle tap together. There would have been instructions in the packs, what did they state. About suppliers, my brother works in a major home store and he is an expert on tiling, flooring, plumbing, electrics, carpentry, stoves etc etc. He has never held a hammer let alone a nail in his life, he has never laid a floor etc etc. But my god he can talk the talk to get a sale, anything to sell the product, anything to make it sound he knows what he's talking about.

Didn't stipulate it in the enclosed installation sheet but had seen it mentioned elsewhere. Supplier had suggested the gap every 3 boards but went with every 4. They have closed up a small bit. Maybe I just need to give it time