Should Invisalign buttons disrupt my normal bite? My first left the practice and this disrupted my treatment.

Depending on the position of the attachment on the tooth it
is possible for it to interfere with full closure while it stays on the tooth. Most
of the materials used for the attachments are much weaker than your teeth so
the worst case scenario would be you wearing down the attachment itself. You
can see if your doctor may be can remove some material from it to see if that
would help.

You should be able to close your teeth together without hitting the Invisalign buttons. You might need a mid-course correction. I'm not sure why your lower teeth were not done at the same time as your uppers.