Levelling a sterling board floor

[camerart]

Hi,
I laid a sterling board floor, but some of the edges are different levels, by a couple of mm. This will have sheets of underlay, then laminate or vinyl. Will a couple of mm show or does it need to be level?
Camerart

 

[big-all]

the edges should always be joined on a joist or other timber so if they are not level have you checked for debris or old nails for example stopping the boards going flat when screwed down

 

[camerart]

the edges should always be joined on a joist or other timber so if they are not level have you checked for debris or old nails for example stopping the boards going flat when screwed down

Hi A,
This was glued down to a concrete floor.
C