OK, regardless of whether you hold any particular heretic to be Catholic or not, Pope Pius XII teaches that membership in the Church is limited only those who:
1) Are baptized
And
2) Profess the true Faith
And
3) Have not been so unfortunate as to separate themselves from the unity of the Body
Or
4) Have not been excluded by legitimate authority for grave faults committed
So, if any one of the four things is lacking a person is not a member of the Church.
Do you agree with this?
As long as #1 and #2 is present, that person is a member of the Church.
#3 is the definition of excommunication:
"Excommunication is the gravest of all canonical punishments ; it separates the delinquent from the communion of the faithful, and, practically speaking, deprives him of all the rights of membership in the Church of Christ." Still a member.
#4 is the censure of excommunication decreed by a Church authority. Still a member.
You have a conundrum, which is why you simply ignore it.....your conundrum is: If a Catholic committed the sin of heresy, that person is a Catholic with the sin of heresy on his soul. Should he decide to repent, he can go to confession and be absolved, something only members can do. The nature of the sin makes this unlikely.
One must accept that heresy is a sin, the worst of all the sins, but that is what heresy is, a sin, one that Catholics can always be absolved of in confession.
All you gotta do is use yourself as an example, it is not complicated. You would need to explain how you (only using you for the purpose of an example only, no insult intended), a Catholic with the sin of heresy on your soul, can go to confession at all, and also be absolved of the sin of heresy if you are not a member of the Church.
I expect you will continue to ignore this, but there it is regardless.