Answered Can I change the starting layer of a print

It is possible, not usually worth it to me.
Here are some options.

https://community.ultimaker.com/topic/6219-2-ways-to-resume-print-from-last-layer/

https://www.3dhubs.com/talk/thread/how-rescue-print-stopped-mid-way

https://hackaday.com/2014/08/02/restarting-3d-prints/

You can in some slicers simply sink the print below the bed in the preview and when it slices the bits below the surface will not print.

(not that you gave enough detail to know which approach is what you are after, but there are ways to do it)

 

See if the sink it through the bed trick works in your slicer then (it does in several, Simplify3D being one of those -- I have not tested the others, but folks say ...).

 

if it does not (I assume mattercontrol and never had luck with it just working so doubt it does the fancy stuff) download the netfabb free edition, its a trial, at the end of the trail do the non licensed version if you dont want to pay for it but you can just cut off whatever height on Z you want. Meshmixer also does this.