So, when the Pope resigns, the Apostolic See is not yet vacant. It only become "lawfully vacant" upon "the death of the Pope." 

You still haven't posted any actual evidence for this.  You keep posting regs related to when a pope dies.  

You still haven't posted any actual evidence for this.  You keep posting regs related to when a pope dies. 

The Apostolic See is made up of more offices that just the Pope. So, even if the Pope resigns his office, those other people in the other offices that make up the Apostolic See (as defined in Canon 861) have not resigned. So, if the Pope alone resigns his office, the Apostolic See is not vacant because the other offices that make up the Apostolic See (according to Canon 861) are not vacant. Those other offices (the ones discussed in Canon 861) do not become vacant until AFTER the Pope dies (which law you can find in UDG 14, and Pastor Bonus 6). 

So, Canon 861, UDG 14, and Pastor Bonus 6, all explain the process and require that it be nothing other than that.

Please tell me why you think that a papal resignation (Canon 332) creates a vacancy in the Apostolic See. Please show me your "regs" for that. You will not find any. You are just assuming that it works a certain way, but that is not how the law says it works.

You're seriously playing the expert on canon law and you can't find this notorious canon? It's canon 844. I'll even provide you with the rest of the "magisterium" of your "popes."

https://tinyurl.com/mhfm-communion-non-catholics
Canon 844.4, 1983 Code of Canon Law:
“If the danger of death is present or other grave necessity, in the judgment of the diocesan bishop or the conference of bishops, Catholic ministers may licitly administer these sacraments to other Christians who do not have full communion with the Catholic Church, who cannot approach a minister of their own community and on their own ask for it, provided they manifest Catholic faith in these sacraments and are properly disposed.”[6]
Canon 844.3, 1983 Code of Canon Law:
“Catholic ministers may licitly administer the sacraments of penance, Eucharist, and anointing of the sick to members of the oriental churches which do not have full communion with the Catholic Church, if they ask on their own for the sacraments and are properly disposed. This holds also for members of other churches, which in the judgment of the Apostolic See are in the same condition as the oriental churches as far as these sacraments are concerned.”[7]

Vatican II docuмent, Orientalium Ecclesiarum # 27:
“Given the above-mentioned principles, the sacraments of Penance, Holy Eucharist, and the anointing of the sick may be conferred on eastern Christians who in good faith are separated from the Catholic Church, if they make the request of their own accord and are properly disposed.”[2]

John Paul II, Catechism of the Catholic Church (# 1401):
“… Catholic ministers may give the sacraments of Eucharist, Penance, and Anointing of the Sick to other Christians not in full communion with the Catholic Church…”[4]

I repeat, do you accept the solemn, constant, universal teaching of your sect and its canon law that non-Catholics may receive Holy Communion or are you a hypocrite?

Canon 853 (1917 Code) used the phrase "any baptized person." Why do you think it did not use the phrase "any baptized Catholic?"

You suggested it would be impossible under the 1917 Code to admit non-Catholics to the Sacraments. That is not correct. Under the 1917 Code, non-Catholics could be admitted to the Sacraments unless they did not meet the requirements of Canon 731.2:

"731 § 2. it is forbidden that the Sacraments of the Church be ministered to heretics and schismatics, even if they ask for them and are in good faith, unless beforehand, rejecting their errors, they are reconciled with the Church."

So, it speaks of people who are "heretics and schismatics," not just "members of the oriental churches" and "other Christians who do not have full communion with the Catholic Church."

Please notice that the language used is different in the two Codes, and 1983 code better reflects the fact that not all people who are "members of" other Churches are automatically guilty of "heresy" and "schism." Some of those "members of" the other Churches might be clueless about the differences between their faith that they grew up with in Siberia and the Catholic faith. So, as long at they "make the request of their own accord and are properly disposed," they are allowed to receive Holy Communion. 

And so, the 1983 code is not really talking about the same people as the 1917 code. But clearly a professed "heretic" or "schismatic" will not be someone who is "properly disposed" even in 1983 canon law, because by definition in 1983 canon law "heresy" and "schism" merit automatic excommunication.

Admittedly, the phrase "properly disposed" in 1983 Code is extremely vague. But so is the phrase "reconciled with the Church" in the 1917 Code. In fact, to be "reconciled" implies that the person was at one time a Catholic and voluntarily leave the Church. We would not say that a person who grew up in Siberia, never seeing a Catholic church, would need to be reconciled with the Church, right?

Anyway, the language in Canon 853 (1917 Code) expresses the possibility that non-Catholics, in certain circuмstances, can receive Holy Communion.

I’m not judging anything.  Church officials have said that pope x is pope.  As a catholic, I either obey that judgment or act schismatically.  End of story. 

I’m not opposed to sedevacantism (ie Fr Chazal's sede-impoundism or sede-privationism) but there are limits to what laity/priests can decide.  Many of you go far, far beyond those limits.  That’s the problem. 

If Jorge Bergoglio were to publicly admit that he knows he publicly teaches heresy but refuses to step down and the cardinals and bishops refused to do anything about it, would you still accept him as pope?