The problem was observed in textproc/dikt. Before r469254 this port had PORTVERSION= 2l3 When in this condition PORTVERSION was changed to DISTVERSION= 2s1 portlint complained: > $ portlint -C > FATAL: Makefile: dikt-2.s1 < dikt-2l3_2. Choose another PORTVERSION or bump PORTEPOCH. > 1 fatal error and 0 warnings found. This is wrong because 2l3 < 2s1. There are very few versions in this format, but it looks like portlint doesn't handle them correctly.
I'm closing this as not a bug. The bug was in the port using DISTVERSION to begin with.