Stated in lease agreement, B. Lease payments paid late 3 times within a 12-month period create a default of the lease agreement. Will this stand up if I serve the notice to evict.

Depends on the area and type of rental, but in general yes,
Are they paying all of the late fees each time they pay late.
I mention this, since I have had regular renters who pay late almost every month, I make a lot of money off late fees,
** well did when I owned the rentals.

Has not paid any of the late fees, haha now I see them posting to see if I really could.

Sure it would stand up because without that clause a person could be evicted for being late even once.

Hmmm Compers posts as the landlord, Batty posts as both the tenant AND landlord.

(see: https://www.askmehelpdesk.com/real-estate-law/breech-lease-agreement-621508.html)

Something strange is going on here.