bumping PORTREVISION does not seem to make a lot of sense as the only thing you changed is moving to github. Either the commit hash you choose is the one corresponding to 1.004, and in that case, it is the exact same thing, or it is not 1.004 and in that case PORTVERSION should have been changed.

There are identical, I've checked. But I think that bump is ok, unless old rule that you bump when package change (WWW in this case) doesn't true anymore.

WWW is metadata, we do not bump solely on metadata changes. A bit like MAINTAINER change, you never see anyone bumping for MAINTAINER change.